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Robotic Spacecraft (Astronomy, Planetary, Earth, Solar/Heliophysics) => Space Science Coverage => Topic started by: jebbo on 05/16/2013 04:21 pm

Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 05/16/2013 04:21 pm
Given recent events on Kepler, it seems like a good idea to start looking at the replacement missions.  So here is a starter on TESS.

There is a reasonable summary from Ricker et al here: https://arxiv.org/abs/1406.0151
Overview of the orbit design: here (http://spaceflight101.com/tess/tess-orbit-design/)
Latest expected science yield (numbers of planets detected, etc): https://arxiv.org/abs/1804.05050
Main archive page: here (https://archive.stsci.edu/tess/)

Note: I will update this post to add further links to the archive manual, target catalogues, etc as they become available.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: MarsMethanogen on 07/27/2017 04:06 pm
Link doesn't appear to work at my end.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: AnalogMan on 07/27/2017 05:56 pm
Link doesn't appear to work at my end.

Looks like the link expired since it was posted 4 years ago.  Here's a copy of the presentation.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: gongora on 04/16/2018 02:31 am
Bumping this thread for post-launch TESS updates
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: Joffan on 04/18/2018 11:56 pm
Both solar arrays deployed following separation, TESS is a live spacecraft.

(launch thread (https://forum.nasaspaceflight.com/index.php?topic=45038.msg1812127#msg1812127))

Pre-launch TESS science briefing

https://www.youtube.com/watch?v=3zPuashuEfE
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: redliox on 04/19/2018 01:28 am
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: Zed_Noir on 04/19/2018 08:35 am
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.

Keep in mind that the TESS targets are suppose to be within a few hundred light years range.

Think the Northern ans Southern Celestial poles gets more coverage from the fixed field of view of the cameras. There are notable longitude coverage gaps in the TESS search sphere area during the initial 2 year primary mission period.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: jebbo on 04/19/2018 09:01 am
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.

I expect they will pick around 6,000 stars to monitor at 2 minute cadence in the polar regions.  I've updated the top post with the latest expected yield paper - this is well worth a read.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: jebbo on 04/19/2018 09:03 am
Think the Northern ans Southern Celestial poles gets more coverage from the fixed field of view of the cameras. There are notable longitude coverage gaps in the TESS search sphere area during the initial 2 year primary mission period.

Hmm ... I don't think I'd describe the small longitude gaps as "notable" (see figure 7 of the Riker paper in the top post).

There is a 6 degree *latitude* gap at the ecliptic equator.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: Zed_Noir on 04/19/2018 10:23 am
Think the Northern ans Southern Celestial poles gets more coverage from the fixed field of view of the cameras. There are notable longitude coverage gaps in the TESS search sphere area during the initial 2 year primary mission period.

Hmm ... I don't think I'd describe the small longitude gaps as "notable" (see figure 7 of the Riker paper in the top post).

There is a 6 degree *latitude* gap at the ecliptic equator.

--- Tony
Did see the coverage area on the TESS search sphere area on a NASA youtube clip. Estimate that the missing longitude coverage area comes to about 2 to 3 camera field of view area.

The ecliptic equator belt got coverage from Kepler. But the reason the Celestial poles gets more coverage also applies to the omitted ecliptic equator belt coverage.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: speedevil on 04/19/2018 10:29 am
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.

A period of constant observation gives the best results. The design of the camera results in each scan  having two poles of constant observation.
This is also used in that those poles are going to be in depth observed for JWST targetting.
Title: Re: NASA - Transiting Exoplanet Survey Satellite updates
Post by: Ben the Space Brit on 04/19/2018 10:52 am
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.

Primarily nearby red and brown dwarves. I understand that smaller K- and G-class stars drop below visual magnitude at only ~10 parsecs, so there are probably a lot of potential target stars in those areas (the galactic halo) that don't have anything other than instantly-forgettable alphanumeric catalogue numbers.

I would also expect that faint stars are more easily observed towards the galactic poles and away from the optically dazzling OB-class star clouds and the equally bright active hydrogen-alpha and H-II emissions of star-forming regions in the main galactic disc.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/19/2018 11:01 am
Quote
Over the course of the next several weeks, @NASA_TESS will conduct a series of burns (6 of them) to reach its final science orbit. This will include a lunar fly-by on 17 May 2018 at 06:31:52.180 UTC. The lunar fly-by distance will be at approximately 8000 km (altitude).

https://twitter.com/NASA_TESS/status/986921649260941312
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: TakeOff on 04/19/2018 03:32 pm
Given the emphasis TESS will give to the northern and southern celestial poles, I'm curious what targets are out there in those regions.  Kepler (initially) targeted a region just off the Milky Way by comparison.
Maybe the ecliptic poles are better for follow up observations by the great telescopes around the equator, and space telescopes like JWST. The Sun is never in the way and I suppose ground based telescopes can always observe one of the poles at night.


A reason I've heard somewhere, I think from scientists on the project, not just speculating on my own, is that TESS will always be pointing away from the Sun (covering a broad strip from the pole to the equator), making it possible for simultaneous observations from the ground. This is probably more interesting for other astrophysics than transiting planets. TESS will observe the variability of stars and quasar all over the sky. It will for example maybe find stellar mass black holes revealed by them briefly microlensing background stars. That would benefit from immediate observation from the ground. Also, telescopes on completely different wavelengths (for example hunting high energy transient events such as novas) can coordinate observations with TESS' visible light.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/20/2018 04:59 am
A reason I've heard somewhere, I think from scientists on the project, not just speculating on my own, is that TESS will always be pointing away from the Sun (covering a broad strip from the pole to the equator), making it possible for simultaneous observations from the ground.

Yes. There's a decent visualisation of this in the video on the orbit page linked in the top post (starting around 1 min in).

Quote
This is probably more interesting for other astrophysics than transiting planets. TESS will observe the variability of stars and quasar all over the sky. It will for example maybe find stellar mass black holes revealed by them briefly microlensing background stars. That would benefit from immediate observation from the ground. Also, telescopes on completely different wavelengths (for example hunting high energy transient events such as novas) can coordinate observations with TESS' visible light.

The problem for transients is that data is only downloaded every 2 weeks, so occultations & microlensing won't be seen simultaneously from the ground. But novae last long enough that we can get good follow-up.

Transient hunting in the 30-minute cadence FFIs is almost a by-product of the FFI planet search ...
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: avollhar on 04/20/2018 08:19 am
TESS downlink signal has been detected by UHF-Satcom and Scott Tilley (IMAGE re-discoverer):

https://twitter.com/uhf_satcom/status/987062005667385344 (https://twitter.com/uhf_satcom/status/987062005667385344)
https://twitter.com/coastal8049/status/987094571560546304 (https://twitter.com/coastal8049/status/987094571560546304)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/21/2018 12:31 pm
Quote
Yesterday, @NASA_TESS had its Star Trackers turned on and Attitude Control System transitioned to Coarse Pointing Inertial. Attitude thrusters were pulsed in preparation for the first #TESS on orbit burn.

https://twitter.com/nasa_tess/status/987658735798640640
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: Svetoslav on 04/22/2018 08:09 pm
The @NASA_TESS first apogee maneuver (A1M) was successfully completed yesterday. This burn was a 50 second checkout burn to characterize the performance of the #TESS thrusters.

https://twitter.com/NASA_TESS/status/988146812908261376
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/22/2018 10:05 pm
Quote
[email protected]_TESS current speed (at about 22 Apr 2018 15:46 UTC / 11:46 AM EST) was approximately 0.373 km/s. It will be increasing until #TESS reaches perigee at about 25 Apr 2018 05:42 UTC / 1:42 PM at which point it will be approximately 9.51 km/s.

https://twitter.com/nasa_tess/status/988157793898201089
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/23/2018 04:30 pm
Quote
Yesterday @NASA_TESS performed star tracker to gyro / Reaction Wheel Assemblies (RWA) calibration. Observatory is performing great with no issues. #TESS

https://twitter.com/NASA_TESS/status/988450606087057408?s=19 (https://twitter.com/NASA_TESS/status/988450606087057408?s=19)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/24/2018 12:30 pm
Quote
[email protected]_TESS remains in Coarse Pointing Inertial, all subsystems are nominal. #TESS continues to make contact with the Deep Space Network. The on-board orbit propagator was initialized and is now running. Additional observatory subsystems are planned for check out today.

https://twitter.com/NASA_TESS/status/988752668347813893 (https://twitter.com/NASA_TESS/status/988752668347813893)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/25/2018 12:02 pm
Quote
[email protected]_TESS successfully completed the first perigee maneuver (PM1). Initial indications are that the burn was nominal. P1M is the second of six on orbit burns for #TESS to reach its final science orbit.

https://twitter.com/NASA_TESS/status/989111041001967618
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/26/2018 06:12 am
Quote
[email protected]_TESS Mission Update: The Ka-band transmitter and Traveling Wave Tube Amplifier were turned on. @NASASCaN's Deep Space Network successfully locked on to the Ka signal immediately. The link showed a strong link margin with no errors.

https://twitter.com/NASA_TESS/status/989297254262624256 (https://twitter.com/NASA_TESS/status/989297254262624256)

Quote
[email protected]_TESS Mission Update: The #TESS ADHU (data handling unit computer for the instrument from @SEAKR_Eng) was turned on. Checkout confirmed all nominal. #TESS sent data from the ADHU to the Ka Transmitter and received packets at DSN without errors.

https://twitter.com/NASA_TESS/status/989315773981175810 (https://twitter.com/NASA_TESS/status/989315773981175810)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/29/2018 03:43 pm
Quote
TESS is approaching its second apogee - at 1903 UTC today it will be 353440 km above the Earth's surface and start on the downward arc of its second orbit.

https://twitter.com/planet4589/status/990616006568632320
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 04/30/2018 06:33 am
Quote
[email protected]_TESS Mission Update: Team decided that the second apogee maneuver (Apogee 2 maneuver (A2M)), was not necessary based on the good system performance during the first two maneuvers. Spacecraft subsystems continue to operate nominally.

https://twitter.com/nasa_tess/status/990743720566894594
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/30/2018 07:45 am
Useful!

Quote
We present new gravity and limb-darkening coefficients for a wide range of effective temperatures, gravities, metallicities, and microturbulent velocities. These coefficients can be used in many different fields of stellar physics as synthetic light curves of eclipsing binaries and planetary transits, stellar diameters, line profiles in rotating stars, and others. The limb-darkening coefficients were computed specifically for the photometric system of the space mission TESS and were performed by adopting the least-square method. In addition, the linear and bi-parametric coefficients, by adopting the flux conservation method, are also available. On the other hand, to take into account the effects of tidal and rotational distortions, we computed the passband gravity-darkening coefficients y(λ) using a general differential equation in which we consider the effects of convection and of the partial derivative (∂lnI(λ)/∂lng)Teff. To generate the limb-darkening coefficients we adopt two stellar atmosphere models:
ATLAS (plane-parallel) and PHOENIX (spherical, quasi-spherical, and r-method).
The specific intensity distribution was fitted using five approaches: linear, quadratic, square root, logarithmic, and a more general one with four terms. These grids cover together 19 metallicities ranging from 10−5 up to 10+1 solar abundances, 0 ≤ log g ≤ 6.0 and 1500 K ≤ Teff ≤ 50000 K. The calculations of the gravity-darkening coefficients were performed for all plane-parallel ATLAS models.

https://arxiv.org/abs/1804.10295 (https://arxiv.org/abs/1804.10295)

Note: I'll update later to add the FTP links for Tables 2-29, which are the actual Limb Darkening coefficients.

Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: Ben the Space Brit on 04/30/2018 10:47 am
Quote
[email protected]_TESS Mission Update: Team decided that the second apogee maneuver (Apogee 2 maneuver (A2M)), was not necessary based on the good system performance during the first two maneuvers. Spacecraft subsystems continue to operate nominally.

https://twitter.com/nasa_tess/status/990743720566894594

So, basically, TESS's main propulsion system is working better than expected; that's good to know!
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 04/30/2018 11:57 am
Quote
[email protected]_TESS Mission Update: The four cameras for #TESS are now powered on and will begin collecting data for the calibration process which will last until mid June.

https://twitter.com/NASA_TESS/status/990922086913839105 (https://twitter.com/NASA_TESS/status/990922086913839105)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: Joffan on 04/30/2018 07:46 pm
Quote
[email protected]_TESS Mission Update: Team decided that the second apogee maneuver (Apogee 2 maneuver (A2M)), was not necessary based on the good system performance during the first two maneuvers. Spacecraft subsystems continue to operate nominally.

https://twitter.com/nasa_tess/status/990743720566894594

So, basically, TESS's main propulsion system is working better than expected; that's good to know!

Better than worst-case-viable, for sure, good news. Currently a 9-day orbit so they have two more perigees and one more apogee to tune the course for the lunar flyby 17 May.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: redliox on 04/30/2018 08:05 pm
Excellent to hear fewer burns are needed.  This will raise the prospects of extending TESS after the primary mission.  :)  I can hardly wait for June now!
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: eeergo on 05/01/2018 01:07 am

Given recent events on Kepler, it seems like a good idea to start looking at the replacement missions.  So here is a starter on TESS.


There is a reasonable summary from Ricker et al here: https://arxiv.org/abs/1406.0151
Overview of the orbit design: here (http://spaceflight101.com/tess/tess-orbit-design/)
Latest expected science yield (numbers of planets detected, etc): https://arxiv.org/abs/1804.05050
Main archive page: here (https://archive.stsci.edu/tess/)


Note: I will update this post to add further links to the archive manual, target catalogues, etc as they become available.


--- Tony
From the new article in the OP: "A Revised Exoplanet Yield from the Transiting Exoplanet Survey Satellite (TESS)".

Quote
The MIT-led Transiting Exoplanet Survey Satellite (TESS) has a goal of detecting terrestrial-mass planets orbiting stars bright enough for mass determination via ground-based radial velocity observations. Here we present estimates of how many exoplanets the TESS mission will detect, physical properties of the detected planets, and the properties of the stars that those planets orbit. This work uses stars drawn from the TESS Input Catalog Candidate Target List and revises yields from prior studies that were based on Galactic models. We model the TESS observing strategy to select approximately 200,000 stars at 2-minute cadence, while the remaining stars are observed at 30-min cadence in full-frame image data. We place zero or more planets in orbit around each star, with physical properties following measured exoplanet occurrence rates, and use the TESS noise model to predict the derived properties of the detected exoplanets. In the TESS 2-minute cadence mode we estimate that TESS will find 1250 ± 70 exoplanets (90% confidence), including 250 smaller than 2 Earth-radii. Furthermore, we predict an additional 3200 planets will be found in full-frame image data orbiting bright dwarf stars and more than 10,000 around fainter stars. We predict that TESS will find 500 planets orbiting M-dwarfs, but the majority of planets will orbit stars larger than the Sun. Our simulated sample of planets contains hundreds of small planets amenable to radial velocity follow-up, potentially more than tripling the number of planets smaller than 4 Earth-radii with mass measurements. This sample of simulated planets is available for use in planning follow-up observations and analyses.


Daniel Marin has an excellent review (in Spanish):

http://danielmarin.naukas.com/2018/05/01/cuantos-exoplanetas-descubrira-tess/ (http://danielmarin.naukas.com/2018/05/01/cuantos-exoplanetas-descubrira-tess/)


Quote
Resumiendo, TESS descubrirá cerca de 15.000 planetas extrasolares, pero solo 4.500 serán de “calidad”, o sea, podrán ser analizados en profundidad más adelante usando otros instrumentos, que es el objetivo prioritario de la misión. Pero lo más fascinante es que muchos estarán alrededor de estrellas brillantes, algunas de las cuales se podrán ver a simple vista o con unos simples prismáticos. Dentro de poco será muy común mirar al cielo, señalar una estrella casi al azar y decir “ahí hay un planeta”. Y todo gracias a TESS.

In summary, TESS will discover around 15 thousand extrasolar planets, but only 4500 will be "high-quality"; that is, will be amenable to in-depth further analyses using other instruments - which is the mission's objective. The most fascinating thing, however, is that many will be orbiting brighter stars, some of which can be seen with the naked eye or with some simple binoculars. Soon, it will be common to look at the sky, point almost randomly at a star and say "there is a planet there". All thanks to TESS.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/01/2018 06:12 am
That paper is linked in the top post
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: eeergo on 05/01/2018 06:13 am
That paper is linked in the top post

Oops, I didn't check the OP. I'll modify my message.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/01/2018 06:17 am
No problem ... it's a great paper and well worth repeating!!

Edit: I'll also change the top post to make it clearer that is gives the expected numbers, etc
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/01/2018 12:01 pm
Quote
[email protected]_TESS Mission Update: The #TESS team were successful in putting TESS in Fine Pointing Mode (instrument supplying quaternions) for the first time as part of instrument commissioning.

https://twitter.com/NASA_TESS/status/991285551025348609 (https://twitter.com/NASA_TESS/status/991285551025348609)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: deruch on 05/07/2018 05:46 am
Quote from: Date: 2018-05-04
[email protected]_TESS Mission Update: #TESS continued fine pointing data collection for instrument calibration. The #TESS cameras are being slowly cooled to their operating temperature of -80°C.
https://twitter.com/NASA_TESS/status/992465126031847424

Quote from: Date: 2018-05-06
[email protected]_TESS Mission Update: completed the P2M (Perigee 2 Maneuver), another on orbit burn to place #TESS into its final science orbit, nominally. The instrument is turned off for all maneuvers. While this maneuver is only for 7 secs it puts TESS on target for our lunar encounter.
https://twitter.com/NASA_TESS/status/993290408829517824
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: deruch on 05/07/2018 05:47 am
An Estimate of the Yield of Single-Transit Planetary Events from the Transiting Exoplanet Survey Satellite
Steven Villanueva Jr., Diana Dragomir, B. Scott Gaudi
Quote
We present a semi-analytic estimate of the expected yield of single-transit planets from the Transiting Exoplanet Survey Satellite (TESS). We use the TESS Candidate Target List 6 (CTL-6) as an input catalog of over 4 million sources. We predict that from the 200,000 stars selected to be observed with the high-cadence postage stamps with the highest CTL-6 priority, there will be 241 single-transit events caused by planets detectable at a signal-to-noise ratio of SNR≥7.3. We find a lower limit of an additional 977 events caused by single-transit planets in the full frame images (FFI); this is a lower limit because the CTL-6 is incomplete below a TESS magnitude of T>12. Of the single-transit events from the postage stamps and FFIs, 1091/1218 will have transit depths deeper than 0.1%, and will thus be amenable for photometric follow-up from the ground, and 1195/1218 will have radial velocity signals greater than 1 m/s. We estimate that the periods of 146 single transits will be constrained to better than 10% using the TESS photometry assuming circular orbits. We find that the number of planets detected by TESS in the postage stamps with periods P>25 days will be doubled by including single-transiting planets, while the number of planets with P>250 days will be increased by an order of magnitude. We predict 79 habitable zone planets from single-transits, with 18 orbiting FGK stars.
https://arxiv.org/abs/1805.00956
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/09/2018 10:18 am
Quote
[email protected]_TESS Mission Update: After P2M (Perigee 2 Maneuver) was completed, the spacecraft is in Coarse Pointing Inertial mode. Pointing is stable and all spacecraft systems are nominal. The cameras are on and taking data, and are continuing cooling to approximately -85C.

https://twitter.com/NASA_TESS/status/994159146374172673 (https://twitter.com/NASA_TESS/status/994159146374172673)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/14/2018 10:50 am
Quote
[email protected]_TESS Mission Update: The spacecraft is in Coarse Pointing Inertial mode, with the instrument ensemble boresight at -54deg pitch. Battery is healthy and between 33.1-33.3V. No spacecraft activities yesterday, the cameras are on and taking data, and have reached -85C ± 1C.

https://twitter.com/NASA_TESS/status/995979301915897857 (https://twitter.com/NASA_TESS/status/995979301915897857)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/15/2018 07:44 am
Quote
[email protected]_TESS Mission Update: Perigee 3 Maneuver (P3M) was completed successfully with nominal performance from the thrusters.  #TESS is on its way to a lunar flyby at 06:34:35 UTC on 17th May. @NASAMoon here we come!

https://twitter.com/NASA_TESS/status/996209235276025856 (https://twitter.com/NASA_TESS/status/996209235276025856)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: redliox on 05/18/2018 11:44 am
Any news on how yesterday's lunar flyby went?
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 01:10 pm
Latest update is:

Quote
#TESS is on track for a lunar flyby on 17 May at 06:34:35 UTC (2:34 AM EST). At this point, TESS will be 8,253 km from the lunar surface. In the coming days, follow @NASA, @NASAGoddard, @NASAblueshift and @NASA_TESS for more details.

https://twitter.com/NASA_TESS/status/996831284629565441 (https://twitter.com/NASA_TESS/status/996831284629565441)

Presumably went okay, as there's been no signs of worry from any of the team

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 05/18/2018 02:47 pm
Quote
[email protected]_TESS Mission Update: #TESS successfully completed a lunar flyby on May 17. TESS completed scheduled contact with @NASASCaN's Deep Space Network. Post flyby tracking was confirmed. TESS was 8,253.54 km from the surface of the moon at its closest approach.

https://twitter.com/nasa_tess/status/997485558283882501
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 03:17 pm
First test images!

Quote
Hot off the press, @NASA_TESS STARS!!!!
The first TESS test image shown here by @mrtommyb at #chexo #dataisbeautiful

https://twitter.com/elsisrad/status/997495543579533312 (https://twitter.com/elsisrad/status/997495543579533312)

These are 2 second exposures
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 03:19 pm
And a more official source:

Quote
This test image from one of the four cameras aboard @NASA_TESS captures a swath of the southern sky along the plane of our galaxy. Imagine how many new #exoplanets TESS will find once we enter into science operations! #TESS

https://twitter.com/NASA_TESS/status/997496257227689985 (https://twitter.com/NASA_TESS/status/997496257227689985)

Quote
JUST IN: I’m excited to share the first image from one of the four cameras aboard @NASA_TESS, our new planet-hunting satellite! You’re looking at more than 200,000 stars in this remarkable image: https://go.nasa.gov/2Grw0q5

https://twitter.com/JimBridenstine/status/997495576534056960 (https://twitter.com/JimBridenstine/status/997495576534056960)

The bright star at the bottom is beta Centauri
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 03:30 pm
Quote
As part of camera commissioning, the #TESS science team snapped a two-second  test exposure using one of the four @NASA_TESS cameras. A  science-quality image, also referred to as a “first  light” image, is expected to be released in June. Enjoy this preview! @TESSatMIT

https://twitter.com/NASA_TESS/status/997499375084556290 (https://twitter.com/NASA_TESS/status/997499375084556290)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 03:40 pm
An annotated image:

Quote
Here's the @NASA_TESS with FITS header thanks to http://astrometry.net  . Do science with it at your own peril 😉 http://nova.astrometry.net/user_images/2117266#annotated

https://twitter.com/jegpeek/status/997501292649074689 (https://twitter.com/jegpeek/status/997501292649074689)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: webdan on 05/18/2018 03:46 pm
Just down from center... moving object?
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 04:13 pm
Just down from center... moving object?

There are a few others. Probably a cosmic ray track
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: jebbo on 05/18/2018 04:41 pm
Further to the annotated image, here is where it is in the sky:

Quote
If you want to see the image in context, here it is placed on the sky in WorldWide Telescope: https://t.co/VvKcqKzQ0O https://t.co/qtc8sbCUeS

https://twitter.com/Alex_Parker/status/997514292286099456?s=19 (https://twitter.com/Alex_Parker/status/997514292286099456?s=19)
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: matthewkantar on 05/18/2018 10:02 pm
Just down from center... moving object?

Looks like it, cool.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: webdan on 05/18/2018 10:26 pm
Just down from center... moving object?

Looks like it, cool.

Actually, as jebbo posted, there are others. I wasn't thorough enough to fully check when posting but they are there.
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: FutureSpaceTourist on 05/19/2018 01:04 am
NASA has released a higher-res version
Title: Re: NASA - Transiting Exoplanet Survey Satellite (TESS) updates
Post by: webdan on 05/19/2018 03:10 am
NASA has released a higher-res version

Obligatory “My God, it’s full of stars”

Thanks for posting this!

Edit 5/20: Two second exposure (about 200k stars) so definitely no asteroid trails.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: FutureSpaceTourist on 05/19/2018 07:28 pm
Quote
[email protected]_TESS Mission Update: Based on great performance from the lunar fly-by, no adjustment burn is required. The next maneuver is the Period Adjust Maneuver (PAM) on May 30th; it will put #TESS into final science orbit. Observatory is in Coarse Pointing Mode operating nominally.

https://twitter.com/nasa_tess/status/997921651906969601
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: FutureSpaceTourist on 06/01/2018 06:13 pm
Quote
[email protected]_TESS Mission Update:  The Period Adjust Maneuver (PAM) was completed successfully on May 30th. The burn was confirmed as nominal. No trajectory adjustment maneuver will be required. Success! #TESS is in its final lunar resonant orbit!

https://twitter.com/nasa_tess/status/1002603655722397696
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: redliox on 06/03/2018 03:40 am
Grand to hear it is in orbit and the mission beginning  :D
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: FutureSpaceTourist on 06/04/2018 05:15 am
Quote
[email protected]_TESS Mission Update: The #TESS team are now assessing the final orbit to understand long term eclipse predictions and other parameters that can be used in planning the two year survey for #exoplanets.

https://twitter.com/nasa_tess/status/1003485273710301186
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hick2 on 06/21/2018 02:45 pm
Quote
@NASA_TESS Mission Update: #TESS continues to operate in its science orbit that was reached in May. In  one of the last passes, TESS performed a "break dance:" rotating around to evaluate any stray light sources to characterize camera performance for the duration of the mission.

https://twitter.com/NASA_TESS/status/1009789588116770816
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: TakeOff on 06/26/2018 09:45 am
When will the first data be downloaded? NASA's TESS mission website doesn't advertise it. Should be now end of June, right? Why is it so quite about it? Isn't it supposed to have discovered a bunch of exoplanets already on the first run?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jgoldader on 06/26/2018 12:08 pm
There’s always a lot of calibration work that has to be done, both on the spacecraft side (pointing and such) and the instrument.  There could also be outgassing, and you have to wait for things to settle down.  Finally, it’s one thing to run your PSF-fitting (photometry) and transit detection algorithms on simulated data, but you need to make sure everything works on real data.  All these things take time.  I’m sure the team is anxious to get data out the door, but I’m just as sure they want to get it right first.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jcm on 06/26/2018 12:13 pm
There’s always a lot of calibration work that has to be done, both on the spacecraft side (pointing and such) and the instrument.  There could also be outgassing, and you have to wait for things to settle down.  Finally, it’s one thing to run your PSF-fitting (photometry) and transit detection algorithms on simulated data, but you need to make sure everything works on real data.  All these things take time.  I’m sure the team is anxious to get data out the door, but I’m just as sure they want to get it right first.

Exactly. I don't know anything for sure, but my understanding is that they are still commissioning the instruments doing calibrations and so on, making sure they have everything they need. My guess is that the first science run will begin Jul 10 and complete a month later.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 06/26/2018 01:10 pm
I wouldn't expect anything straight away after commissioning either as presumably they'll be looking to do ground-based followup to reject false-positives.  This is a more serious issue for TESS over Kepler.
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 06/26/2018 04:00 pm
I wouldn't expect anything straight away after commissioning either as presumably they'll be looking to do ground-based followup to reject false-positives.  This is a more serious issue for TESS over Kepler.

In an article sourced from Astronomy Now magazine March 2018 principle investigator George Ricker stated that the first batch of discoveries will be ready to be released by the end of 2018. He also stated that it would begin the first part of its survey in June. With Tess launching later than expected you can probably just add a month onto these.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: TakeOff on 06/26/2018 06:54 pm
Okay, so real science data will take a while. But when TESS will make its first perigee?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 06/26/2018 09:24 pm
According to the TESS Observatory Guide (PDF) (https://heasarc.gsfc.nasa.gov/docs/tess/docs/TESS_observatory_guide_v1.1.pdf):

Quote
The instrument calibration phase nominally ends on day 55 after launch. TESS will then begin science collection with an initial science test orbit and data downlink. Science operations and the collection of data in the first observing sector are expected to start day 68 of the mission.

If that plan was followed, science operations started yesterday, June 25th.

[Edit: Just to be clear, I'd guess that Jonathan probably knows better than the guide, and that he thinks it's going to be another orbit before science ops start is a pretty good sign of that being how it is]

I've been watching the DSN and saw a 1Mb/s downlink from TESS on Sunday, June 24th. It looked like about 1.2GB of data was received. Don't know if that was the perigee for the initial test orbit or not. I know the downlink speed for TESS is supposed to be much higher than that, though (100Mb/s).  Right now though, it looks like TESS's fast rate is 1Mb/s, and it's slow rate is 16Kb/s.

when TESS will make its first perigee?

TESS has completed two 13.7 day orbits since its final adjustment maneuver.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 06/30/2018 01:07 pm
I wouldn't expect anything straight away after commissioning either as presumably they'll be looking to do ground-based followup to reject false-positives.  This is a more serious issue for TESS over Kepler.
Has any thought been given to timing the observations early on so GAIA and TESS fields overlap for a pointing?
Or did it not work out to be plausible/useful
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 06/30/2018 05:39 pm
I assume you mean K2 rather than Gaia, which is all sky?

Kepler's K2 can only observe in the ecliptic plane to maintain stability.  This is the one part of the sky TESS does not observe!

There will however be small overlaps on the edges of K2's fields, though I doubt the TESS obs have been designed to happen simultaneously.  Scientifically there isn't a huge benefit though, they're still going to want to do follow-up anyway as even Kepler can be fooled if the background eclipsing binary is close enough.

Edit: Here's a map of the overlaps (in red);
https://twitter.com/lacalaca85/status/910234769421676544
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 06/30/2018 06:40 pm
I assume you mean K2 rather than Gaia, which is all sky?
Gaia is all-sky, but it does not cover the whole sky at once, and has a much different scan than TESS.
The similar wavelength sensors (IIRC), and broadly comparable resolutions would seem to be a good check, if there was an overlap early in commissioning.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 06/30/2018 07:02 pm
But the next Gaia data release won't be until after TESS has finished it's primary mission.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 06/30/2018 07:20 pm
I don't see what benefit there would be to simultaneous Gaia-TESS observations.  Gaia has a considerably better pixel scale than TESS but Gaia would only provide a single epoch and thus not be able to characterise any background time-variant phenomena.  It would not be able to confirm TESS transits.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 06/30/2018 07:47 pm
But the next Gaia data release won't be until after TESS has finished it's primary mission.

TESS all being well I saw quoted can it’s calculated last in operations for over thirty years due to its orbit.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 06/30/2018 08:55 pm
http://sci.esa.int/gaia/58784-exoplanets/

Quote
Surveys to search for transiting exoplanets are usually designed so that the observations of the parent stars are frequent – to catch as many transits as possible. The way that Gaia surveys the sky means that it will observe each star an average of 70 times during the five years of the nominal mission but when and how often the observations are made will be determined by the scanning law and cannot be changed. However, if a star is orbited by a transiting planet, then a few observations acquired by the satellite during transits might be sufficient to obtain a detection.

Scientists predict that, with the precision of Gaia's photometric measurements [6], it will be possible to discover a few hundred to a few thousand transiting, massive planets of the hot Jupiter and very hot Jupiter types. These are gaseous giant planets, about the mass of Jupiter, that orbit their parent star at very short distances, much smaller than the distance of Mercury from the Sun, completing one orbit on time scales of a few days.

So TESS would have to change it's field to match that of GAIA, but what's the point when by the time that GAIA releases it's data TESS has already scanned all of it's fields?

Note that GAIA's exoplanet list won't be released until the end of 2022. It might be possible to match some single transits seen in both TESS and GAIA to narrow down the orbital period for longer period planets, but by then TESS should hopefully be well into it's extended mission, scanning fields for longer periods of time (there are several options for the extended mission).

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: hop on 06/30/2018 09:26 pm
Another mission with the potential to overlap slightly with TESS is NEOWISE. One pole at least should overlap for any amount of time they are in simultaneous operation.

NEOWISE is supposed to end soon (or perhaps has already ended? IIRC seeing "June 2018" but can't find a good reference) when the orbit drifts into an orientation negatively impacted by scattered light.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 07/02/2018 10:09 am
Plato should also overlap, given how long TESS might last.  In this case, TESS might be a reasonable "scout" for Plato, identifying interesting fields for Plato to stare at

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Tomness on 07/02/2018 06:32 pm
Quote
@LucaPlanets
9 hours ago

The orbit adjust burns of @NASA_TESS were 10 times more precise than expected! It was so good that the spacecraft has fuel for >20 years of stable operations (!!) #Exoplanets2

CROSS REFRENCING
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 07/04/2018 06:58 am
Early flight results have been downloaded and analysed and were previewed at Exoplanets2 here in Cambridge. But they are embargoed.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/04/2018 08:22 am
Early flight results have been downloaded and analysed and were previewed at Exoplanets2 here in Cambridge. But they are embargoed.

--- Tony

Are you allowed to say when to?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Svetoslav on 07/04/2018 08:47 am
I do hope we won't have another Kepler debacle. I hope a reasonable period will be decided, and then the data will be distributed to 3rd parties and the public.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/04/2018 08:57 am
I do hope we won't have another Kepler debacle. I hope a reasonable period will be decided, and then the data will be distributed to 3rd parties and the public.

Completely agree with you there.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 07/04/2018 03:50 pm
I do hope we won't have another Kepler debacle. I hope a reasonable period will be decided, and then the data will be distributed to 3rd parties and the public.

There is a difference between early results released by the team and when the data will be publicly available.  The data won't be public until the beginning of next year.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/04/2018 07:20 pm
I do hope we won't have another Kepler debacle. I hope a reasonable period will be decided, and then the data will be distributed to 3rd parties and the public.

There is a difference between early results released by the team and when the data will be publicly available.  The data won't be public until the beginning of next year.

That’s not was said previously. It was stated results would be available at the end of this year.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 07/04/2018 09:09 pm
The last official statement was Jan 2019.  But regardless whether it's December/January the point is it's still many months away.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 07/05/2018 10:46 pm
TESS is supposed to release data quickly for ground based RV follow up. Recent papers from RV surveys that I've read talk about December as the first release. No big deal if it doesn't happen until the next month (anyway, let the staff have a holiday at that time of year) Releases should be regular from then.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: redliox on 07/06/2018 01:04 am
TESS is supposed to release data quickly for ground based RV follow up. Recent papers from RV surveys that I've read talk about December as the first release. No big deal if it doesn't happen until the next month (anyway, let the staff have a holiday at that time of year) Releases should be regular from then.

*shrugs* I'm willing to wait for decent results.  TESS is going to take, what was it, at least 2 years for its survey, if not longer?  Likewise the Kepler team didn't want to release false positives, and some time was spent waiting for their data.  For now all I want is to know TESS is in its proper orbit and beginning aforementioned survey.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Svetoslav on 07/10/2018 09:01 pm
Hmm... is there something wrong with TESS?

Via Eric Berger: The @NASA_TESS mission has been awfully quiet of late. I inquired today if anything was wrong. The totality of the reply I received is thus:

"NASA will be issuing an update on TESS tomorrow (Wednesday) by noon EDT. I will send you a link when it’s live."

https://twitter.com/SciGuySpace/status/1016785065311956992
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: rory on 07/10/2018 10:40 pm
Seems likely they're just releasing those embargoed results from Exoplanets II.

Quote from: Cesar Baima on Twitter
An astronomer who is my source and is working with Tess data posted yesterday this photo of preliminary results from the mission in a seminar yesterday, so I guess everything is OK...
https://twitter.com/SoCiencia/status/1016807170170654721
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: paolozamparutti on 07/11/2018 05:56 am
Hmm... is there something wrong with TESS?

Via Eric Berger: The @NASA_TESS mission has been awfully quiet of late. I inquired today if anything was wrong. The totality of the reply I received is thus:

"NASA will be issuing an update on TESS tomorrow (Wednesday) by noon EDT. I will send you a link when it’s live."

https://twitter.com/SciGuySpace/status/1016785065311956992

academics who have access to the Tess mailing list assure me everything is ok

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: FutureSpaceTourist on 07/11/2018 04:40 pm
Quote
July 11, 2018
NASA’s TESS Spacecraft Continues Testing Prior to First Observations

After a successful launch on April 18, 2018, NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite, is currently undergoing a series of commissioning tests before it begins searching for planets. The TESS team has reported that the spacecraft and cameras are in good health, and the spacecraft has successfully reached its final science orbit. The team continues to conduct tests in order to optimize spacecraft performance with a goal of beginning science at the end of July. 

Every new mission goes through a commissioning period of testing and adjustments before beginning science operations. This serves to test how the spacecraft and its instruments are performing and determines whether any changes need to be made before the mission starts observations.

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory in Lexington, Massachusetts; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

For the latest updates on TESS, visit nasa.gov/tess.

https://www.nasa.gov/feature/goddard/2018/nasa-s-tess-spacecraft-continues-testing-prior-to-first-observations
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 07/27/2018 05:14 pm
And so it begins.

https://tess.mit.edu/news/nasas-tess-spacecraft-starts-science-operations/
Quote
NASA’s Transiting Exoplanet Survey Satellite has started its search for planets around nearby stars, officially beginning science operations on July 25, 2018. TESS is expected to transmit its first series of science data back to Earth in August, and thereafter periodically every 13.5 days, once per orbit, as the spacecraft makes it closest approach to Earth. The TESS Science Team will begin searching the data for new planets immediately after the first series arrives.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Targeteer on 07/28/2018 04:29 am
TESS has a Facebook page

https://www.facebook.com/NASATESS/?hc_ref=ARTUWXqaI5z32KvsSpcQ0bCsmNCuF8QBbGnItRXu82AZmNo0qsaxaaOd15QbMDVtld8&fref=nf
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 07/28/2018 11:20 pm
TESS: Transiting Exoplanet Survey Satellite - Elisa Quintana (NASA GSFC) (https://www.youtube.com/watch?v=IkaEFmFFd9I)

Commissioning took a month longer than initially planned, which has pushed the first public data release of the first four months data back from December to early 2019 (as mentioned several posts back). Hoping that the science team can try to find a way to release the data early.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: quasarquantum on 08/14/2018 09:46 am
Data of the first science orbit has been downlinked on 8. August. TESS caught a comet :)
https://tess.mit.edu/news/catching-a-comet-how-the-tess-science-office-found-c-2018-n1/ (https://tess.mit.edu/news/catching-a-comet-how-the-tess-science-office-found-c-2018-n1/)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Nomadd on 08/24/2018 06:58 pm
 I had a chance to ask Jeff Volosin about comparing Kepler transits with TESS versions of the same planet to help calibrate analysis of both and he said NASA declined because they wanted to keep TESS on the southern hemisphere for now.
 Next year they should have a chance to get some Kepler targets with TESS for comparison.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 08/25/2018 02:08 am
I had a chance to ask Jeff Volosin about comparing Kepler transits with TESS versions of the same planet to help calibrate analysis of both and he said NASA declined because they wanted to keep TESS on the southern hemisphere for now.
 Next year they should have a chance to get some Kepler targets with TESS for comparison.

He also said that:

* The quality of imagery has been much better than expected: the science they'd expected to be reserved for 20,000 stars they'd specially selected per section instead should be doable on just about any star visible in the field of view.

* The one-month delay on full science ops was for a pointing problem (since resolved).  I think he said this was from unexpected jitter when using the reaction wheels.

* Even having to dump momentum from the reaction wheels three times as often (three times per orbit instead of once), he expects to have over 100 years of propellant reserves. Which is nice. The numbers here are 40kg of propellant (thanks to very good insertion ops), 10 grams of propellant per momentum dump maneuver.

I'd be interested to know if TESS is using ceramic bearings in its reaction wheels, (https://www.youtube.com/embed/KibT-PEMHUU) which might help it get a little closer to that hundred years ;)

Edit: Remembered a bit more:

* First public data release in ~2 months

* The TESS project has funding set aside to do radial velocity from ground telescopes as a follow-on to planet discovery

* TESS images 24x90 degrees of sky at 0.5fps for ~28 days per section.  Volosin expects that to be handy for a lot of folks.  E.g. he expects to record a supernova from start to finish at 0.5fps.

* Volosin seems totally in favor of looking in certain directions for much longer than 28 days, after the two-year survey mission is over. (see some possible extended missions on pages 1-3 of this great PDF (https://arxiv.org/pdf/1705.08891.pdf))
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Quagga on 08/25/2018 09:50 am

* The quality of imagery has been much better than expected: the science they'd expected to be reserved for 20,000 stars they'd specially selected per section instead should be doable on just about any star visible in the field of view.

* Even having to dump momentum from the reaction wheels three times as often (three times per orbit instead of once), he expects to have over 100 years of propellant reserves. Which is nice. The numbers here are 40kg of propellant (thanks to very good insertion ops), 10 grams of propellant per momentum dump maneuver.


These are great news. What effect does this have on the expected planet yield?

Edit: Also, does this mean TESS will be more sensitive towards smaller planets in wider orbits?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: deruch on 09/01/2018 06:03 pm
* TESS images 24x90 degrees of sky at 0.5fps for ~28 days per section.  Volosin expects that to be handy for a lot of folks.  E.g. he expects to record a supernova from start to finish at 0.5fps.

So far as I understand it, that's not how their cameras/sampling work.  Your Field of View description is close enough (it's actually 24x96 deg.) as is the pointing (~28 days/section).  But the imaging rates are way off.  TESS's cameras do take images at 0.5fps--or rather they have a 2 second exposure time--but then those images are stacked and summed.  For the targeted investigation of stars, that summing takes 60 frames (taken over 120 seconds) sums the image then has pre-selected postage stamps-which will include the areas around targeted stars-cut out.  It's those postage stamps which are saved.  For the full FOV images, TESS stacks and sums the full 900 frames taken over 30 minutes but then saves the whole image instead of only the targeted parts.  So, while the cameras are operating at 0.5fps, the actual images that are being saved/transmitted are more like 0.5 images/minute or 2 images/hour (only I don't know how exactly to describe the stacked and summed images).  TESS is most likely to catch a supernova in the full field images.  To catch one in the background of one of the postage stamps would be extremely lucky.  So, the 2 images/hour is really the best bet. 

The image on their Goddard mission page explains it better: 
https://heasarc.gsfc.nasa.gov/docs/tess/operations.html#time-sampling
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 09/01/2018 07:50 pm
From IAU 2018 General Assembly via Twitter (https://twitter.com/AllPlanets/status/1034046852201496576);
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/03/2018 09:43 am
So far as I understand it, that's not how their cameras/sampling work. 

Yup. Your description is correct ... short cadence image every 2 minutes; FFI every 30 minutes.

Images are downlinked every 14 days, which limits the usefulness as a supernova alert mechanism.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: deruch on 09/03/2018 05:09 pm
So far as I understand it, that's not how their cameras/sampling work. 

Yup. Your description is correct ... short cadence image every 2 minutes; FFI every 30 minutes.

Images are downlinked every 14 days, which limits the usefulness as a supernova alert mechanism.

--- Tony

I don't think anyone was thinking of using them as an alert mechanism.  But they will very likely catch and document one with saved images every 30 minutes from the Full Frame Images (FFI).  My struggle is how to differentiate between what TESS is actually doing and just saying that they'll take 1 FFI picture every 30 minutes.  Because TESS's FFIs are really a combined image where they take the 900 frames shot over those 30 minutes (each frame shot over a 2 second exposure time), sum them up into a single image and then just store that for later transmission.  So, the cameras are capturing the supernova progression at 0.5 fps, but then through the summing action they lose that really fine time resolution.  Regardless, the images of a developing supernova at a 30 minute cadence will be really cool.  And if they somehow get lucky enough to see one in the background of the postage stamps--and thereby have images every 2 minutes--that would be awesome.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 09/03/2018 11:30 pm
So, the cameras are capturing the supernova progression at 0.5 fps, but then through the summing action they lose that really fine time resolution.  Regardless, the images of a developing supernova at a 30 minute cadence will be really cool.  And if they somehow get lucky enough to see one in the background of the postage stamps--and thereby have images every 2 minutes--that would be awesome.
I guess it depends how much storage and processor they have free onboard.
64 megapixels for example, if you have ten prior frames stored, and have enough spare CPU to threshold every few frames to see if anything has popped up five sigma and add it to a list of areas to store postage stamps around that area at 0.5s  until it quiets down.

I am probably not awake, but am failing to find detailed instrument and computational subsystem info, and if there is any emergency low bitrate channel that could in principle give prompt alerts of interesting places to look, even if downlinking much data is prohibitive.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: LouScheffer on 09/04/2018 01:32 am
So, the cameras are capturing the supernova progression at 0.5 fps, but then through the summing action they lose that really fine time resolution.  Regardless, the images of a developing supernova at a 30 minute cadence will be really cool.  And if they somehow get lucky enough to see one in the background of the postage stamps--and thereby have images every 2 minutes--that would be awesome.
I guess it depends how much storage and processor they have free onboard.
64 megapixels for example, if you have ten prior frames stored, and have enough spare CPU to threshold every few frames to see if anything has popped up five sigma and add it to a list of areas to store postage stamps around that area at 0.5s  until it quiets down.

I am probably not awake, but am failing to find detailed instrument and computational subsystem info, and if there is any emergency low bitrate channel that could in principle give prompt alerts of interesting places to look, even if downlinking much data is prohibitive.
There is no way that I know of to signal the ground on request of the spacecraft.   The ground needs to have an antenna pointed towards the spacecraft and listening, which is scheduled every two weeks.   Using DSN (the normal path for communications) for continuous coverage is not practical - the network is already over-subscribed, and it would be too expensive in any event.   Maybe they could hire USN or another commercial vendor, but this likely has the same problems. 

The best bet would be to build three dedicated ground stations, spaced 120 degrees apart, so at least one is always listening.   Since the spacecraft never comes closer to the Earth than 100,000 kilometers, three are enough so one is always in view.  Bit rate would be very low, since (a) these antennas cannot be huge or they would cost too much, and (b) the spacecraft does not normally have the high gain antenna pointed to Earth, so the low gain antenna would need to be used.  But it would then be possible to signal at any time.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: hop on 09/04/2018 05:02 am
I am probably not awake, but am failing to find detailed instrument and computational subsystem info, and if there is any emergency low bitrate channel that could in principle give prompt alerts of interesting places to look, even if downlinking much data is prohibitive.
I would expect they get some low bandwidth telemetry outside of the downlink period (the NG fact sheet (http://www.northropgrumman.com/Capabilities/ScienceEnvironmentSatellites/Pages/default.aspx) mentions an S band transmitter), but even if possible in theory, there's essentially zero chance significant operational or flight software changes would be made to support something like this in the prime mission. TESS was funded to find exoplanets, everything else is a bonus. Maybe in an extended extended extended mission if it really lasts for decades as some have suggested...

The 30 minute FFIs will already be a goldmine for all sorts of astronomy.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: acsawdey on 09/04/2018 03:26 pm
The best bet would be to build three dedicated ground stations, spaced 120 degrees apart, so at least one is always listening.   Since the spacecraft never comes closer to the Earth than 100,000 kilometers, three are enough so one is always in view.  Bit rate would be very low, since (a) these antennas cannot be huge or they would cost too much, and (b) the spacecraft does not normally have the high gain antenna pointed to Earth, so the low gain antenna would need to be used.  But it would then be possible to signal at any time.

Perhaps it could employ a beacon like New Horizons does during it's hibernation periods -- broadcast just a carrier wave and the center frequency tells you if it has an alert. No demodulation equipment necessary would make it easier to recruit people to check in a few times a day. Not as good as instantly, but ~8 hours notice is better than 14 days.

It does seem like on-board analysis could as speedevil suggests and dynamically add postage stamps if something new pops up between one 2-second frame and the next (and persists for the next few frames).
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: as58 on 09/04/2018 05:29 pm
The best bet would be to build three dedicated ground stations, spaced 120 degrees apart, so at least one is always listening.   Since the spacecraft never comes closer to the Earth than 100,000 kilometers, three are enough so one is always in view.  Bit rate would be very low, since (a) these antennas cannot be huge or they would cost too much, and (b) the spacecraft does not normally have the high gain antenna pointed to Earth, so the low gain antenna would need to be used.  But it would then be possible to signal at any time.

Perhaps it could employ a beacon like New Horizons does during it's hibernation periods -- broadcast just a carrier wave and the center frequency tells you if it has an alert. No demodulation equipment necessary would make it easier to recruit people to check in a few times a day. Not as good as instantly, but ~8 hours notice is better than 14 days.

It does seem like on-board analysis could as speedevil suggests and dynamically add postage stamps if something new pops up between one 2-second frame and the next (and persists for the next few frames).

For supernovae 2-second time resolution feels like an overkill and I doubt a supernova could be caught by analysing consecutive frames. Supernova brightening time scales are quite a bit longer than a few seconds.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: LouScheffer on 09/04/2018 07:06 pm

For supernovae 2-second time resolution feels like an overkill and I doubt a supernova could be caught by analysing consecutive frames. Supernova brightening time scales are quite a bit longer than a few seconds.
At least sometimes supernovae are associated with Gamma Ray Bursts, which can have optical transients with risetimes measured in seconds (http://www.slac.stanford.edu/econf/C131113.1/papers/kopac.pdf).  So two second resolution might both be useful, and could get some trigger events with inter frame comparison.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: deruch on 09/07/2018 10:02 pm
I had a chance to ask Jeff Volosin about comparing Kepler transits with TESS versions of the same planet to help calibrate analysis of both and he said NASA declined because they wanted to keep TESS on the southern hemisphere for now.
 Next year they should have a chance to get some Kepler targets with TESS for comparison.

Dr. Jeff Volosin - TESS - 21st Annual International Mars Society Convention
The Mars Society
Published on Sep 3, 2018

Dr. Jeff Volosin, NASA Goddard
Transiting Exoplanet Survey Satellite (TESS)

From the 21st Annual International Mars Society Convention, held at the Pasadena Convention Center in Southern California from Aug 23-26, 2018.

The four-day International Mars Society Convention brings together leading scientists, engineers, aerospace industry representatives, government policymakers and journalists to talk about the latest scientific discoveries, technological advances and political-economic developments that could help pave the way for a human mission to the planet Mars.


https://www.youtube.com/watch?v=KIAYb08qFrI?t=001

https://www.youtube.com/watch?v=KIAYb08qFrI
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 09/15/2018 06:22 pm
50 exoplanet candidates:

Quote
In just six weeks of science observations, NASA’s Transiting Exoplanet Survey Satellite (TESS) has already found 50 possible new worlds for scientists to examine.
http://blogs.discovermagazine.com/d-brief/2018/09/14/nasa-tess-exoplanet-spacecraft-finds-new-worlds/#.W51MuUxFy74
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 09/15/2018 07:44 pm
50 exoplanet candidates:

Quote
In just six weeks of science observations, NASA’s Transiting Exoplanet Survey Satellite (TESS) has already found 50 possible new worlds for scientists to examine.
http://blogs.discovermagazine.com/d-brief/2018/09/14/nasa-tess-exoplanet-spacecraft-finds-new-worlds/#.W51MuUxFy74

Thanks for posting that sounds like TESS is working beyond nominal which is good news for science results.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 09/15/2018 08:22 pm
Dr. Jeff Volosin - TESS - 21st Annual International Mars Society Convention
@17:20 'You can see the rise of a supernova and you can see it tail off. Not to get ahead of ourselves, but we're publishing in the next couple of weeks something around that' - paraphrased.
Just after that he refers again to 'usually you don't have the benefit of a camera which takes data every two seconds' - which is odd for a comment about supernova if there is no triggering on high brightness events, because if there is no fast trigger, then there is no point at all, because by the time the data is downlinked, the next opportunity to observe that spot will often be a couple of years hence, and the only frames stored would be at the low 'full frame' decimated rate.

If you have ten prior frames stored, and have enough spare CPU to threshold every few frames to see if anything has popped up five sigma and add it to a list of areas to store postage stamps around that area at 0.5s  until it quiets down.

Will be interesting to see details in the paper referred to.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/18/2018 07:10 am
Announcement of the first discovery from TESS:

TESS Discovery of a Transiting Super-Earth in the Π Mensae System

Quote
We report the detection of a transiting planet around π Mensae (HD\,39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered planet has a size of 2.14± 0.04~R⊕ and an orbital period of 6.27 days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays a 6.27-day periodicity, confirming the existence of the planet and leading to a mass determination of 4.82± 0.85~M⊕. The star's proximity and brightness will facilitate further investigations, such as atmospheric spectroscopy, asteroseismology, the Rossiter-McLaughlin effect, astrometry, and direct imaging.

Paper here: https://arxiv.org/abs/1809.05967 (https://arxiv.org/abs/1809.05967)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 09/18/2018 08:06 am
Odd it’s been uploaded to arxiv without an official press release.

Edit: oh it’s at the EPSC.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/18/2018 12:05 pm
It's #EPSC2018 but yes, I was a bit surprised this came out with no associated media stuff :-)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ChrisGebhardt on 09/18/2018 09:49 pm
It's #EPSC2018 but yes, I was a bit surprised this came out with no associated media stuff :-)

This is a draft of a not-yet final paper and was not published with permission.  It's an embargo break, and not a good one either.

UPDATE on this (same as posted below).  The person who told me the paper was not published with permission was incorrect.

These are being published by the TESS team themselves so that ground telescopes can be used to quickly confirm the exoplanet candidates.

There was some initial confusion on that point as NASA is not used to operating on such quick turn-around of candidate planet info -- hence why the draft papers are hitting and becoming public hours before NASA tweets confirmation (as opposed to the usual method where NASA announces first or in conjunction with official paper publication).
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: JH on 09/19/2018 12:55 am
Embargo breaks not withstanding, its a cool discovery, with a surface gravity of 105(+24/-22)% that of Earth. A shame that it's exposed to 318x Earth's solar flux.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: as58 on 09/19/2018 03:05 pm
The paper was posted on arxiv by the first author. How does that make it "published without permission"? Or didn't she get ok from the other authors?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/19/2018 03:52 pm
I wondered about that as well. There has been some surprise about the paper, but mostly to do with publication of a discovery from data that is only available to a few beta testers from a mission with no proprietary period ... to me, the paper seems scant on detail of the data and errors properties and the detrending process - especially for a "first discovery" paper.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 09/19/2018 05:08 pm
It does worry you when some of the most intelligent people on Earth can screw up something as simple as an embargo...
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 09/19/2018 06:51 pm
It does worry you when some of the most intelligent people on Earth can screw up something as simple as an embargo...

They are still only human.

Anyway leak or not it has now been reported more widely.

https://gizmodo.com/nasa-s-tess-space-telescope-has-spotted-its-first-exopl-1829165207
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/20/2018 06:17 am
Well, it is now official:

From @NASA_TESS on Twitter:
Quote
The @NASA_TESS team is excited to announce the mission's first candidate  planet -- a super-Earth around the bright star Pi Mensae, nearly 60 light-years away. The planet orbits every 6.3 days. The discovery is now  being reviewed by other scientists to validate it. Stay tuned!
https://twitter.com/NASA_TESS/status/1042496479108243456 (https://twitter.com/NASA_TESS/status/1042496479108243456)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/20/2018 06:18 am
And another one:

TESS Discovery of an ultra-short-period planet around the nearby M dwarf LHS 3844
Quote
Data from the newly-commissioned \textit{Transiting Exoplanet Survey Satellite} (TESS) has revealed a "hot Earth" around LHS 3844, an M dwarf located 15 pc away. The planet has a radius of 1.32±0.02 R⊕ and orbits the star every 11 hours. Although the existence of an atmosphere around such a strongly irradiated planet is questionable, the star is bright enough (I=11.9, K=9.1) for this possibility to be investigated with transit and occultation spectroscopy. The star's brightness and the planet's short period will also facilitate the measurement of the planet's mass through Doppler spectroscopy.

https://arxiv.org/abs/1809.07242 (https://arxiv.org/abs/1809.07242)

Edit: incidentally, there is an AO followup campaign in progress at Keck.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 09/20/2018 08:24 am
Hot Earth, how many of them did we know about before?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/20/2018 08:31 am
Hot Earth, how many of them did we know about before?

Loads ... 614 in the "hot zone" in the 0.8Re - 1.5Re range.

Edit: good visualisation at the PHL (http://phl.upr.edu/projects/habitable-exoplanets-catalog/media/pte)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 09/20/2018 10:45 am
Hot Earth, how many of them did we know about before?

Loads ... 614 in the "hot zone" in the 0.8Re - 1.5Re range.

Edit: good visualisation at the PHL (http://phl.upr.edu/projects/habitable-exoplanets-catalog/media/pte)

Thank you for that especially the link
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/20/2018 01:56 pm
From @NASA_TESS on Twitter:

Quote
A second @NASA_TESS candidate planet has been discovered! Slightly bigger than Earth, this planet orbits LHS 3844, a M dwarf star 49 light-years away, every 11 hours. This find is being reviewed by other scientists, and we're looking forward to studying this cool "hot Earth."

Original tweet (https://twitter.com/NASA_TESS/status/1042773553777664000)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ChrisGebhardt on 09/20/2018 03:00 pm
It's #EPSC2018 but yes, I was a bit surprised this came out with no associated media stuff :-)

This is a draft of a not-yet final paper and was not published with permission.  It's an embargo break, and not a good one either.

UPDATE on this.  The person who told me the paper was not published with permission was incorrect.

These are being published by the TESS team themselves so that ground telescopes can be used to quickly confirm the exoplanet candidates.

There was some initial confusion on that point as NASA is not used to operating on such quick turn-around of candidate planet info -- hence why the draft papers are hitting and becoming public hours before NASA tweets confirmation (as opposed to the usual method where NASA announces first or in conjunction with official paper publication).
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/20/2018 03:59 pm
These are being published by the TESS team themselves so that ground telescopes can be used to quickly confirm the exoplanet candidates.

Both papers use data from the beta test of their Alert system, which is all about speed. This also explains why there are publications from non-public data (all beta testers can see the data) even though there will be no proprietary period.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: deruch on 09/20/2018 08:31 pm
It's #EPSC2018 but yes, I was a bit surprised this came out with no associated media stuff :-)

This is a draft of a not-yet final paper and was not published with permission.  It's an embargo break, and not a good one either.

UPDATE on this.  The person who told me the paper was not published with permission was incorrect.

These are being published by the TESS team themselves so that ground telescopes can be used to quickly confirm the exoplanet candidates.

There was some initial confusion on that point as NASA is not used to operating on such quick turn-around of candidate planet info -- hence why the draft papers are hitting and becoming public hours before NASA tweets confirmation (as opposed to the usual method where NASA announces first or in conjunction with official paper publication).


That's good to know.  Thanks for the update.  Not terribly surprising that there was some confusion as the TESS pipeline is going to be so different from the Kepler one.

You should probably include an edit/correction in the initial post as well.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Chris Bergin on 09/20/2018 09:52 pm
Chris Gebhardt's article (in the right thread):

https://www.nasaspaceflight.com/2018/09/tess-excellent-health-1st-two-exoplanet-first-orbit/
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 09/21/2018 02:46 am
Chris Gebhardt's article (in the right thread):

https://www.nasaspaceflight.com/2018/09/tess-excellent-health-1st-two-exoplanet-first-orbit/

Quote from: the article
While it is not entirely clear what happened after launch, what is known is that the commissioning phase lasted 27 days longer than expected, stretching to the end of July.  TESS’ first science and observational campaign began not in June but on 25 July 2018.


From the end of Jeff Volosin's Mars Society talk: (https://www.youtube.com/watch?v=KIAYb08qFrI?t=1399)

Quote
Volosin: "Performance so far has been excellent. We had a little bit of a problem with our pointing stability. We've since resolved that, and so we're now able to stay pointed appropriately for our mission."

[...]

"We changed the way we dump momentum out of the wheels. We were only supposed to dump momentum once per orbit, but to keep the jitter down we're now doing it three times per orbit.

So that change in ops concepts, every time we dump momentum, we have to use thrusters. And that is the one consumable that we will run out of. We currently have 40kg of fuel onboard because we were so nicely put in our orbit, we didn't need to use a lot of fuel on our own. And so that 40kg of fuel, we use 10g of fuel to dump momentum. So if you calculate that out, we've got a good bit of a hundred years worth of fuel left. So yeah, we're good."

[...]

"So the goal was to get away from the reaction wheels that were used on Kepler, but our reaction wheels had their own problems that induced jitter that we didn't expect. So there is no perfect solution for pointing stability using reaction wheels."


Edit: added one last relevant quote from the talk that I'd missed.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: mlindner on 09/21/2018 03:01 am
Orbital period is 13.7 days so 13.7 days/30 grams * 40,000 grams = ~18,300 days = 50 years
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 09/21/2018 03:39 am
Orbital period is 13.7 days so 13.7 days/30 grams * 40,000 grams = ~18,300 days = 50 years

Might be a combination of info that's mistakenly both pre and post jitter mitigation.  Whether the gram usage is an old value, or the years of fuel left is an old value, or it's something else entirely, I dunno.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 09/21/2018 04:53 am
Also an unrelated quote from that Volosin talk that I had to add.  This from a question about the consequences that flipping the survey space every year has on their long-dwell overlap area.

Quote
Remember for Kepler, they kind of relied on three transits to really prove that it was a planet. So even at the poles, we might only see one, maybe two of a period that's similar to our Earth.  And so what we're hoping is that in an extended mission we would end up spending more time on fields of view that had shown promise.

I knew that some of the extended mission plans were long-dwell, but I hadn't really caught that the mission team was hoping for those extended mission types in particular (there were others), or the fact that they would use the survey to find the best candidates for those dwell regions.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/21/2018 06:01 am
Confirmation of pi Mensae c:

TESS's first planet: a super-Earth transiting the naked-eye star π Mensae
Quote
We report on the confirmation and mass determination of Pi Men c, the first transiting planet discovered by NASA's TESS space mission. Pi Men is a naked-eye (V=5.65 mag), quiet G0 V star that was previously known to host a sub-stellar companion (Pi Men b) on a long-period (Porb=2091 days), eccentric (e=0.64) orbit. Using TESS time-series photometry, combined with GAIA data, published [email protected] Doppler measurements, and archival [email protected] radial velocities, we find that Pi Men c is an inner planet with an orbital period of Porb=6.25 days, a mass of Mp = 4.51 +/- 0.81 MEarth, and a radius of Rp = 1.828+/-0.053 REarth. Based on the planet's orbital period and size, Pi Men c is a super-Earth located at, or close to, the radius gap, while its mass and bulk density suggest it may have held on to a significant atmosphere. Because of the brightness of the host star, this system is highly suitable for a wide range of further studies to characterize the planetary atmosphere and dynamical properties. We also performed a seismic analysis of the TESS light curve and found a hint of an excess power at ~2600 micron-Hz with individual peaks spaced by ~120 micron-Hz. Though the signal-to-noise ratio is very low, this is consistent with the predicted frequency of oscillations for a star of this type, hinting at the asteroseismic potential of the TESS mission.

arxiv (https://arxiv.org/abs/1809.07573)

Edit: oddly, no analysis of active pixel offsets; nor any difference imaging.

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/21/2018 06:02 am
TESS in the Solar System
Quote
The Transiting Exoplanet Survey Satellite (TESS), launched successfully on 18th of April, 2018, will observe nearly the full sky and will provide time-series imaging data in ~27-day-long campaigns. TESS is equipped with 4 cameras; each has a field-of-view of 24x24 degrees. During the first two years of the primary mission, one of these cameras, Camera #1, is going to observe fields centered at an ecliptic latitude of 18 degrees. While the ecliptic plane itself is not covered during the primary mission, the characteristic scale height of the main asteroid belt and Kuiper belt implies that a significant amount of small solar system bodies will cross the field-of-view of this camera. Based on the comparison of the expected amount of information of TESS and Kepler/K2, we can compute the cumulative etendues of the two optical setups. This comparison results in roughly comparable optical etendues, however the net etendue is significantly larger in the case of TESS since all of the imaging data provided by the 30-minute cadence frames are downlinked rather than the pre-selected stamps of Kepler/K2. In addition, many principles of the data acquisition and optical setup are clearly different, including the level of confusing background sources, full-frame integration and cadence, the field-of-view centroid with respect to the apparent position of the Sun, as well as the differences in the duration of the campaigns. As one would expect, TESS will yield time-series photometry and hence rotational properties for only brighter objects, but in terms of spatial and phase space coverage, this sample will be more homogeneous and more complete. Here we review the main analogues and differences between the Kepler/K2 mission and the TESS mission, focusing on scientific implications and possible yields related to our Solar System.
arxiv (https://arxiv.org/abs/1809.07403)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: RotoSequence on 09/21/2018 10:51 am
Edit: oddly, no analysis of active pixel offsets; nor any difference imaging.

--- Tony

Something interesting in their observations that they want to check and re-check before talking about?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 09/21/2018 01:12 pm
Something interesting in their observations that they want to check and re-check before talking about?

Unlikely. APOs and difference images are used to identify false positives, so are a key part of the vetting process. More likely, the analysis is done as part of the default pipeline output and was clean. But I'd still expect a mention.

Edit: two other things occur to me. First, these are very bright stars, so some pixels might be saturated, which makes analysis much more difficult, if not impossible (need to think about this). Second, I don't think the alert data  includes the pixel data
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 09/26/2018 11:02 pm
Exoplanet candidate list grows to 73...

Quote
Astronomers are waiting for independent confirmation from other telescopes, but a surfeit of new planets could be rolling in thanks to a candidate list 73 deep and counting
https://www.smithsonianmag.com/science-nature/tess-space-telescope-will-find-thousands-planets-astronomers-seek-select-few-180970411/
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 10/05/2018 07:47 am
Light curves, Target Pixel Files and validation reports are now available for 44 planet candidates from the Sector 1 observations!

Data is here (https://archive.stsci.edu/prepds/tess-data-alerts/)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 10/05/2018 07:52 am
Similarly, v07.02 of the CTL is now available at MAST.  Links on this (http://archive.stsci.edu/tess/bulk_downloads.html) page.

The release notes for this are here (https://outerspace.stsci.edu/display/TESS/TIC+v7+and+CTL+v7.xx+Data+Release+Notes)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 10/05/2018 07:55 am
Another confirmed planet from TESS:

HD 202772A B: A Transiting Hot Jupiter Around A Bright, Mildly Evolved Star In A Visual Binary Discovered By Tess

Quote
We report the first confirmation of a hot Jupiter discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HD 202772A b. The transit signal was detected in the data from TESS Sector 1, and was confirmed to be of planetary origin through radial-velocity measurements. HD 202772A b is orbiting a mildly evolved star with a period of 3.3 days. With an apparent magnitude of V = 8.3, the star is among the brightest known to host a hot Jupiter. Based on the 27days of TESS photometry, and radial velocity data from the CHIRON and HARPS spectrographs, the planet has a mass of 1.008+/-0.074 M_J and radius of 1.562+/-0.053 R_J , making it an inflated gas giant. HD 202772A b is a rare example of a transiting hot Jupiter around a quickly evolving star. It is also one of the most strongly irradiated hot Jupiters currently known.

Arxiv link (https://arxiv.org/abs/1810.02341)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 10/09/2018 08:40 am
Two TESS papers out today on re-examining the Kepler field:

Prospects for Refining Kepler TTV Masses using TESS Observations
Quote
In this paper we investigate systems previously identified to exhibit transit timing variations (TTVs) in Kepler data, with the goal of predicting the expected improvements to the mass and eccentricity constraints that will arise from combining Kepler data with future data from the TESS mission. We advocate for the use of the Kullback-Leibler (KL) divergence as a means to quantify improvements in the measured constraints. Compared to the original Kepler data, the TESS data will have a lower signal-to-noise ratio, rendering some of the planetary transits undetectable, and lowering the accuracy with which the transit mid-time can be estimated. Despite these difficulties, out of the 55 systems (containing 143 planets) investigated, we predict that the collection of short-cadence data by TESS will be of significant value (i.e. it will improve the mass uncertainty such that the KL divergence is > 0.1) for approximately 6 - 14 planets during the nominal mission, with the range primarily driven by the uncertain precision with which transit mid-times will be recovered from TESS data. In an extended mission this would increase to a total of approximately 12 - 25 planets.
Arxiv link (https://arxiv.org/abs/1810.02852)

Observations of the Kepler Field with TESS: Predictions for Planet Yield and Observable Features
Quote
We examine the ability of the Transiting Exoplanet Survey Satellite (TESS) to detect and improve our understanding of planetary systems in the Kepler field. By modeling the expected transits of all confirmed and candidate planets detected by Kepler as expected to be observed by TESS, we find that TESS has a greater than 50% chance of detecting 277 of these planets at the 3 sigma level in one sector of observations and an additional 128 planets in two sectors. Most of these are large planets in short orbits around their host stars, although a small number of rocky planets are expected to be recovered. Most of these systems have only one known transiting planet; in only ~5 percent of known multiply-transiting systems do we anticipate more than one planet to be recovered. When these planets are recovered, we expect TESS to be a powerful tool to characterizing transit timing variations. Using Kepler-88 (KOI-142) as an example, we show that TESS will improve measurements of planet-star mass ratios and orbital parameters, and significantly reduce the transit timing uncertainty in future years. Since TESS will be most sensitive to hot Jupiters, we research whether TESS will be able to detect tidal orbital decay in these systems. We find two confirmed planetary systems (Kepler-2 b and Kepler-13 b) and five candidate systems that will be good candidates to detect tidal decay.
Arxiv link (https://arxiv.org/abs/1810.02826)

--- Tony

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 11/06/2018 06:13 am
Another discovery:

A Jovian planet in an eccentric 11.5 day orbit around HD1397 discovered by TESS
Quote
The Transiting Exoplanet Survey Satellite TESS has begun a new age of exoplanet discoveries around bright host stars. We present the discovery of HD 1397b (TOI-120.01), a giant planet in an 11.54day eccentric orbit around a bright (V=7.9) G-type subgiant. We estimate both host star and planetary parameters consistently using EXOFASTv2 based on TESS time-series photometry of transits and CORALIE radial velocity measurements. We find that HD 1397b is a Jovian planet, with a mass of 0.419±−0.024 MJup and a radius of 1.023+0.023−0.026$ RJup. Characterising giant planets in short-period eccentric orbits, such as HD 1397b, is important for understanding and testing theories for the formation and migration of giant planets as well as planet-star interactions.
Arxiv link (https://arxiv.org/abs/1811.01882)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: deruch on 11/07/2018 04:52 am
Another discovery:

A Jovian planet in an eccentric 11.5 day orbit around HD1397 discovered by TESS
Quote
...We find that HD 1397b is a Jovian planet, with a mass of 0.419±−0.024 MJup...

That MJup really threw me there for a second.  My brain was very determined to read it as MegaJupiters for a bit.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 11/07/2018 12:24 pm
Another paper on yesterday's discovery:

HD 1397b: a transiting warm giant planet orbiting a V = 7.8 mag sub-giant star discovered by TESS
Quote
We report the discovery of a transiting planet first identified as a candidate in Sector 1 of the Transiting Exoplanet Survey Satellite (TESS), and then confirmed with precision radial velocities. HD1397b has a mass of MP = 0.335+0.018−0.018 MJ, a radius of RP = 1.021+0.015−0.014 MJ, and orbits its bright host star (V=7.8 mag) with an orbital period of 11.53508±0.00057 d, on a moderately eccentric orbit (e = 0.210 ± 0.038). With a mass of M⋆ = 1.284+0.020−0.016 MJ, a radius of R⋆ = 2.314+0.049−0.042 RJ, and an age of 4.7 ± 0.2 Gyr, the solar metallicity host star has already departed from the main sequence. We find evidence in the radial velocity measurements for a long term acceleration, and a P≈18 d periodic signal that we attribute to rotational modulation by stellar activity. The HD1397 system is among the brightest systems currently known to host a transiting planet, which will make it possible to perform detailed follow-up observations in order to characterize the properties of giant planets orbiting evolved stars.
Arxiv link (https://arxiv.org/abs/1811.02156)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 12/06/2018 02:31 pm
Sector 1 and 2 data has now been released to MAST

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 12/06/2018 05:05 pm
And the candidates are available on ExoFOP (https://exofop.ipac.caltech.edu/tess/view_toi.php?sort=toiasc&ipp1=500&page1=1)

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 12/06/2018 11:28 pm
And the candidates are available on ExoFOP (https://exofop.ipac.caltech.edu/tess/view_toi.php?sort=toiasc&ipp1=500&page1=1)

Some neat ones:

16 day period, 9 Earth radii, equilibrium temp 266K (https://exofop.ipac.caltech.edu/tess/target.php?id=272086159)
20 day period, 1.5 Earth radii, equilibrium temp 325K (https://exofop.ipac.caltech.edu/tess/target.php?id=12421862)
51 day period, 1.2 Earth radii, equilibrium temp 171K (https://exofop.ipac.caltech.edu/tess/target.php?id=259962054)
5 day period, 1.7 Earth radii, equilibrium temp 344K (https://exofop.ipac.caltech.edu/tess/target.php?id=305048087)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Semmel on 12/07/2018 08:39 am
Quote
   
TESS Mission Data Now Available http://archive.stsci.edu/archive_news/2018/TESS-12-Dec/index.html

/All data from TESS Observation Sectors 1 and 2 are now publicly available for download with a number of MAST services./

The first batch of Transiting Exoplanet Survey Satellite (TESS) mission data is now available through MAST! This release includes all data from Sectors 1 and 2, observed between July 25 and September 20, 2018. Data products include 2-minute cadence target pixel files (*_tp.fits), extracted light curves (*_lc.fits), and 30-minute cadence full frame images (*_ffic.fits) among others http://archive.stsci.edu/tess/all_products.html. Now, anybody can access these data products, opening an exciting phase of community discovery with TESS data.

https://mast.stsci.edu/tesscut/ /The TESScut tool at MAST/
https://exo.mast.stsci.edu /Light curve previews on exo.MAST/

For a brief overview of MAST services available for TESS data, please see our summary page https://outerspace.stsci.edu/display/TESS/5.0+-+Ways+To+Search+And+Interact+With+TESS+Data+At+MAST. To dive in deeper, the TESS Archive Manual https://outerspace.stsci.edu/display/TESS/TESS+Archive+Manual details the different TESS data products, tutorials on how to use them, and detailed instructions on how to download them from MAST. The official TESS Instrument Handbook https://archive.stsci.edu/missions/tess/doc/TESS_Instrument_Handbook_v0.1.pdf and data release notes for these sectors http://archive.stsci.edu/tess/tess_drn.html are also available.

MAST provides several ways to access TESS data, each with their own specialized purpose:

  * Obtain data for individual targets using the MAST Portal.
    https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html
  * Preview TESS folded light curves for known exoplanets using
    exo.MAST, and find data from complementary MAST missions.
    https://exo.mast.stsci.edu
  * Include TESS data retrieval routines in scripts using the MAST API.
    https://astroquery.readthedocs.io/en/latest/mast/mast.html
  * Obtain a time series of images for any target within TESS FFIs using
    TESScut (avoid downloading the entire sector of data!).
    https://mast.stsci.edu/tesscut/
  * Download all data by Observation Sector or GI Program with Bulk
    Downloads. http://archive.stsci.edu/tess/bulk_downloads.html

The TESS mission https://heasarc.gsfc.nasa.gov/docs/tess/ is a NASA Astrophysics Explorer mission launched by a SpaceX Falcon 9 rocket on April 18, 2018. TESS is currently conducting an all-sky survey for transiting extrasolar planets around nearby and bright stars. TESS will produce an invaluable set of exoplanet candidates, which are highly amenable for follow-up spectroscopic characterization to determine the planet masses and atmospheric compositions. In addition, TESS’s wide-area time-series images will have lasting value for stellar and Galactic astrophysics.

STScI will also be hosting a workshop in February http://www.stsci.edu/institute/conference/tess to provide talks, tutorials, and some hands-on sessions with TESS data. Any further questions on accessing and using TESS mission data products can be submitted to the Archive Helpdesk http://masthelp.stsci.edu/.

http://www.stsci.edu/institute/conference/tess


/Funding for the TESS mission is provided by NASA’s Science Mission directorate. TESS team partners include the Massachusetts Institute of Technology https://tess.mit.edu, the Kavli Institute for Astrophysics and Space Research http://space.mit.edu/space-based-observatories/tess-transiting-exoplanet-survey-satellite, NASA’s Goddard Space Flight Center https://tess.gsfc.nasa.gov, MIT’s Lincoln Laboratory https://www.ll.mit.edu/r-d/projects/transiting-exoplanet-survey-satellite, Orbital ATK http://www.orbitalatk.com, NASA’s Ames Research Center https://www.nasa.gov/ames/tess-pipeline, the Harvard-Smithsonian Center for Astrophysics https://www.cfa.harvard.edu, and the Space Telescope Science Institute https://www.stsci.edu/./

STScI https://twitter.com/MAST_News/ STScI https://www.facebook.com/MASTArchive/ STScI mailto:[email protected]

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 12/12/2018 08:10 pm
A couple of "Neptunes" validated by archival HARPS radial velocity data;

TESS exoplanet candidates validated with HARPS archival data. A massive Neptune around GJ143 and two Neptunes around HD23472 (https://arxiv.org/abs/1812.04501)

Interestingly, the former was recovered in RV data after only a single transit from TESS, which is promising for recovering longer period planets with single transits. The latter will require further RV measurements to constrain the parameters.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 12/13/2018 07:35 am
Sector 3 alerts are now at MAST

https://twitter.com/MAST_News/status/1072638213913755653 (https://twitter.com/MAST_News/status/1072638213913755653)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 12/20/2018 08:55 pm

The independent discovery of planet candidates around low mass stars and astrophysical false positives from the first two TESS sectors (https://arxiv.org/abs/1812.08145)


Quote
Continuous data releases throughout the TESS primary mission will provide unique opportunities for the exoplanet community at large to contribute to maximizing TESS's scientific return via the discovery and validation of transiting planets. This paper introduces our independent detection pipeline of periodic transit events along with the results of its inaugural application to the recently released 2 minute light curves of low mass stars from the first two TESS sectors. The stellar parameters within our sample are refined using precise parallax measurements from the GAIA DR2 which reduces the number of low mass stars in our sample relative to those listed in the TESS Input Catalog. In lieu of the follow-up observations required to confirm or refute the planetary nature of transit-like signals, a validation of transit-like events flagged by our pipeline is performed statistically. The resulting vetted catalog contains seven probable blended eclipsing binaries, eight known TOIs, plus eight new planet candidates smaller than 4 Earth radii. This work demonstrates the ability of our pipeline to detect sub-Neptune-sized planet candidates which to-date, represent some of the most attractive targets for future atmospheric characterization via transmission or thermal emission spectroscopy and for radial velocity efforts aimed at the completion of the TESS level one requirement to deliver 50 planets smaller than 4 Earth radii with measured masses.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 01/08/2019 01:58 am
Quote
The nearby exoplanet, HD 21749b, orbits a bright neighboring star in the Reticulum constellation, with a 36-day orbit and a surface temperature of 300 degrees Fahrenheit. That's actually quite cool, considering how close the planet is to its star.

The discovery was announced Monday at the 233rd meeting of the American Astronomical Society in Seattle.
https://www.cnn.com/2019/01/07/world/tess-mission-first-exoplanet-discoveries/index.html
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: SciNews on 01/08/2019 07:26 am
TESS discovers its third new planet, with longest orbit yet
http://news.mit.edu/2019/tess-discovers-third-planet-0107
Quote
The new planet, named HD 21749b, orbits a bright, nearby dwarf star about 53 light years away, in the constellation Reticulum, and appears to have the longest orbital period of the three planets so far identified by TESS. HD 21749b journeys around its star in a relatively leisurely 36 days, compared to the two other planets — Pi Mensae b, a “super-Earth” with a 6.3-day orbit, and LHS 3844b, a rocky world that speeds around its star in just 11 hours. All three planets were discovered in the first three months of TESS observations.
The surface of the new planet is likely around 300 degrees Fahrenheit — relatively cool, given its proximity to its star, which is almost as bright as the sun.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: whitelancer64 on 01/08/2019 09:42 pm
Quick question: When does TESS look at Alpha Centauri?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 01/09/2019 02:15 am
Sector 11 (2019-Apr-22 to 2019-May-21) and Sector 12 (2019-May-21 to 2019-Jun-19)

But I wouldn't get your hopes up, I can't imagine there'll be much in the way of usable data since Alpha Cen is so bright the CCD will be saturated.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: The Vorlon on 01/09/2019 04:10 am
Tau Ceti would be a nice target too.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: zubenelgenubi on 01/09/2019 05:59 am
Tau Ceti would be a nice target too.
Would this be a cryptic clue from a member of an alien species far older than our own? ;)
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 01/09/2019 06:50 am
NASA Exoplanet Hunter Racks Up Bizarre Worlds and Exploding Stars (https://www.scientificamerican.com/article/nasa-exoplanet-hunter-racks-up-bizarre-worlds-and-exploding-stars/)

Quote
The spacecraft also does more than hunt planets. Mission scientists have studied 101 stars that brightened suddenly, probably because they were exploding supernovae, says Michael Fausnaugh, an astronomer at MIT. Because TESS stares non-stop at one slice of the sky for 27 days, then moves to a neighbouring slice, it captures an unprecedented view of these exploding stars as they brighten and then dim.

“Based on the brightness and shape of that flare, there’s a lot of science that can be done,” Fausnaugh says. For instance, astronomers can scrutinize the way in which the light increases for clues to the type of star that exploded to create a particular flash. TESS discovered six supernovae in just its first month of observing; its predecessor, NASA’s Kepler space telescope, discovered five over the course of four years, Fausnaugh says.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 01/09/2019 07:32 pm
NASA Exoplanet Hunter Racks Up Bizarre Worlds and Exploding Stars (https://www.scientificamerican.com/article/nasa-exoplanet-hunter-racks-up-bizarre-worlds-and-exploding-stars/)

Other highlights from that article:

Quote
TESS works better than team members had dared to dream, says George Ricker, a physicist at MIT and the mission’s principal investigator. Its four cameras can see objects 20% fainter, and focus more sharply, than originally expected. [...]

His team is now writing a proposal to NASA asking that TESS’s mission be extended past its initial two years. That deadline for the proposal was 1 February—but the ongoing partial US government shutdown means Ricker isn’t sure how that timing could change.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 01/09/2019 09:34 pm
NASA Exoplanet Hunter Racks Up Bizarre Worlds and Exploding Stars (https://www.scientificamerican.com/article/nasa-exoplanet-hunter-racks-up-bizarre-worlds-and-exploding-stars/)

Other highlights from that article:

Quote
TESS works better than team members had dared to dream, says George Ricker, a physicist at MIT and the mission’s principal investigator. Its four cameras can see objects 20% fainter, and focus more sharply, than originally expected. [...]

His team is now writing a proposal to NASA asking that TESS’s mission be extended past its initial two years. That deadline for the proposal was 1 February—but the ongoing partial US government shutdown means Ricker isn’t sure how that timing could change.

TESS is guaranteed to be extended, the interesting thing will be which observation plan they settle on for the extended mission. Personally I'd like them to extend the time on the current sectors ... they could extend the ~1 year observing of the Northern hemisphere to ~2 years, thus finding longer distance planets. I think it's more likely that they'll target the galactic plane which is currently missed by the initial survey.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Alpha_Centauri on 01/10/2019 12:08 am
George Ricker mentioned in the press conference that their current plans are to cover part of the ecliptic plane in the next extension.  Unfortunately part of the ecliptic will not be visible until further mission extensions as the Earth will be in the way.

Ultimately the highest value targets are rocky planets in the habitable zone. Since TESS is only sensitive to rocky planets orbiting M dwarfs, which have short-period habitable zones, it makes sense to view more regions of the sky and collect more JWST targets than extend the time baseline right now.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Dao Angkan on 01/10/2019 12:47 am
Ooops ... I said galactic plane, but meant ecliptic plane as "Alpha_Centauri" mentioned.

And yes, TESS wants to find rocky planets, but if it could find larger planets further out, then chances are that smaller planets further in would have similar inclinations and could be potentially found by follow-up transit surveys. Still ... TESS should last for a few decades, so should eventually do many follow-on extended missions.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 01/10/2019 07:05 am
It should find some larger planets in longer period orbits by "lucky transits" where we see a single transit only.  Assuming we can see the ingress and egress slopes, this should give a reasonable guess at period.

--- Tony
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 01/10/2019 12:01 pm
It moves on from an observation after 27 days, can this period be altered so that it stares at a patch of sky for longer periods?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 01/10/2019 12:29 pm
It moves on from an observation after 27 days, can this period be altered so that it stares at a patch of sky for longer periods?

There is overlap for longer than 27 days in certain zones (up to a year). Anyways, haven't seen this NASA article posted:

(https://exoplanets.nasa.gov/system/internal_resources/details/original/1069_Pi_Mensae_c.gif)
Quote
The first confirmed discovery is a world called Pi Mensae c about twice Earth’s size. Every six days, the new planet orbits the star Pi Mensae, located about 60 light-years away and visible to the unaided eye in the southern constellation Mensa. The bright star Pi Mensae is similar to the Sun in mass and size.


(https://exoplanets.nasa.gov/system/internal_resources/details/original/1066_LHS_3884b.gif)
Quote
Next is LHS 3884b, a rocky planet about 1.3 times Earth’s size located about 49 light-years away in the constellation Indus, making it among the closest transiting exoplanets known. The star is a cool M-type dwarf star about one-fifth the size of our Sun. Completing an orbit every 11 hours, the planet lies so close to its star that some of its rocky surface on the daytime side may form pools of molten lava.

Quote
The confirmed planet, HD 21749b, is about three times Earth’s size and 23 times its mass, orbits every 36 days, and has a surface temperature around 300 degrees Fahrenheit (150 degrees Celsius). “This planet has a greater density than Neptune, but it isn’t rocky. It could be a water planet or have some other type of substantial atmosphere,” explained Diana Dragomir, a Hubble Fellow at MKI and lead author of a paper describing the find. It is the longest-period transiting planet within 100 light-years of the solar system, and it has the coolest surface temperature of a transiting exoplanet around a star brighter than 10th magnitude, or about 25 times fainter than the limit of unaided human vision.
https://exoplanets.nasa.gov/news/1542/nasas-tess-rounds-up-its-first-planets-snares-far-flung-supernovae/
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hungry4info3 on 01/29/2019 01:02 am
Five low-mass planet candidates orbiting TYC 8856-192-1 (TOI-125), two of which have been confirmed.
https://arxiv.org/abs/1901.09092
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hungry4info3 on 01/30/2019 10:19 am
An Eccentric Massive Jupiter Orbiting a Sub-Giant on a 9.5 Day Period Discovered in the Transiting Exoplanet Survey Satellite Full Frame Images
https://arxiv.org/abs/1901.09950

TOI-172 = TYC 6932-301-1
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 02/13/2019 06:22 am
We found two new exoplanets! (using TESS) - Cool Worlds

https://www.youtube.com/watch?v=WmOBwNmim1w
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 02/22/2019 08:09 pm
An Exoplanet With an 11-Hour Orbit
Friday, February 1, 2019
Science Update - A look at CfA discoveries from recent journals
The Transiting Exoplanet Survey Satellite (TESS) was launched on April 18 of last year with the primary objective of discovering transiting planets smaller than Neptune around stars bright enough for spectroscopic investigations of their masses and atmospheres. Before TESS there were roughly 385 exoplanets known with masses smaller than Neptune, with orbital periods ranging from less than half-a-day to about two Earth-years.

CfA astronomers Dave Latham, Samuel Quinn, Dave Charbonneau, Jonathan Irwin, Kristo Ment, Jennifer Winters, Martin Paegert, Dimitar Sasselov, and Willie Torres and a large team of TESS collaborators report that TESS has found a "hot Earth" exoplanet, rocky in composition, only about fifty light-years away and orbiting its dwarf star in a mere eleven hours. The planet has a radius of about 1.3 Earth-radii, enough to host an atmosphere, but its short orbital period means it lies very close to its star – only about seven stellar radii. The inferred surface temperature is about 800 kelvin, rather hot to be able to retain an atmosphere but possible. The scientists note, however, that if the planet had formed in roughly this close-in location, its atmosphere would likely have been stripped away in the star’s youth when it was more luminous and had more intense chromospheric activity. In any case, the planet's proximity to us offers the opportunity of characterizing any atmosphere it might have using transit and occultation spectra of the source and the result, interesting in its own right, would also shed light on the planet's formation.

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 04/09/2019 08:33 pm
The hunt is on for closest Earth-like planets (http://news.cornell.edu/stories/2019/03/hunt-closest-earth-planets)

Quote
A team of astronomers from Cornell, Lehigh University and Vanderbilt University has identified the most promising targets for this search in the new “TESS Habitable Zone Star Catalog,” published March 26 in Astrophysical Journal Letters. Lead author Lisa Kaltenegger, professor of astronomy in the College of Arts and Sciences and director of Cornell’s Carl Sagan Institute, is a member of the TESS science team.

The catalog identifies 1,822 stars for which TESS is sensitive enough to spot Earth-like planets just a bit larger than Earth that receive radiation from their star equivalent to what Earth receives from our sun. For 408 stars, TESS can glimpse a planet just as small as Earth, with similar irradiation, in one transit alone.

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 04/15/2019 07:54 pm
TESS Delivers Its First Earth-sized Planet and a Warm Sub-Neptune* (https://iopscience.iop.org/article/10.3847/2041-8213/ab12ed/meta)

The future of exoplanet science is bright, as Transiting Exoplanet Survey Satellite (TESS) once again demonstrates with the discovery of its longest-period confirmed planet to date. We hereby present HD 21749b (TOI 186.01), a sub-Neptune in a 36 day orbit around a bright (V = 8.1) nearby (16 pc) K4.5 dwarf. TESS measures HD 21749b to be ${2.61}_{-0.16}^{+0.17}$ R ⊕, and combined archival and follow-up precision radial velocity data put the mass of the planet at ${22.7}_{-1.9}^{+2.2}$ M ⊕. HD 21749b contributes to the TESS Level 1 Science Requirement of providing 50 transiting planets smaller than 4 R ⊕ with measured masses. Furthermore, we report the discovery of HD 21749c (TOI 186.02), the first Earth-sized (${R}_{p}={0.892}_{-0.058}^{+0.064}{R}_{\oplus }$) planet from TESS. The HD 21749 system is a prime target for comparative studies of planetary composition and architecture in multi-planet systems.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hungry4info3 on 04/15/2019 11:34 pm
Worth noting that this is the same system reported by Trifonov, et al. (https://arxiv.org/abs/1812.04501) as GJ 143, though they weren't able to confirm the planetary nature of the ~Earth-mass planet (Discussed on this forum here (https://forum.nasaspaceflight.com/index.php?topic=31927.msg1887508#msg1887508)).
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 05/23/2019 06:31 am
 Three exocomets discovered around the star Beta Pictoris (https://warwick.ac.uk/newsandevents/pressreleases/three_exocomets_discovered)

Quote
Three extrasolar comets have been discovered around the star Beta Pictoris, 63 light years away, by an international team including a University of Warwick researcher.

Analysis of data from the current NASA mission TESS has revealed the objects for the first time thanks to Sebastian Zieba and Konstanze Zwintz from the Institute of Astro- and Particle Physics at the University of Innsbruck, together with colleagues from Leiden University (Netherlands) and the University of Warwick (UK).

Here’s the related paper.

https://arxiv.org/abs/1903.11071v1
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 06/07/2019 07:26 pm
Dr. Jeff Volosin - TESS - 21st Annual International Mars Society Convention
@17:20 'You can see the rise of a supernova and you can see it tail off. Not to get ahead of ourselves, but we're publishing in the next couple of weeks something around that' - paraphrased.
Just after that he refers again to 'usually you don't have the benefit of a camera which takes data every two seconds' - which is odd for a comment about supernova if there is no triggering on high brightness events, because if there is no fast trigger, then there is no point at all, because by the time the data is downlinked, the next opportunity to observe that spot will often be a couple of years hence, and the only frames stored would be at the low 'full frame' decimated rate.

If you have ten prior frames stored, and have enough spare CPU to threshold every few frames to see if anything has popped up five sigma and add it to a list of areas to store postage stamps around that area at 0.5s  until it quiets down.

Will be interesting to see details in the paper referred to.

I have just looked, and found no mention on arxiv of any supernova detections with TESS that were not done using full-frame images at 30minute cadences. (searching on TESS supernova)
I am unsure what the above phrasing was referring to about 'two seconds' in the context of publication.
In principle, TESS could have regions uploaded to it to watch following a ground detection. This does not appear to have been done.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jg on 06/07/2019 07:38 pm
I will be meeting with the TESS group next week, if anyone has a particularly burning question for them...

I have an agenda of my own, of course, so don't expect me to ask more than a few quick questions...

                                           - Jim
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 06/07/2019 10:17 pm
I will be meeting with the TESS group next week, if anyone has a particularly burning question for them...

I have an agenda of my own, of course, so don't expect me to ask more than a few quick questions...

As implied by the above posts 'What would change if you weren't limited by DSN bandwidth' ?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: theinternetftw on 06/08/2019 02:50 am
I will be meeting with the TESS group next week, if anyone has a particularly burning question for them...

Have they narrowed down what regimes they'd prefer for an extended mission?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: PahTo on 06/08/2019 05:46 am

How do we better resolve inner system rocky worlds?  Resolve includes atmospheric composition.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: speedevil on 06/08/2019 11:54 am

How do we better resolve inner system rocky worlds?  Resolve includes atmospheric composition.

TESS is not going to be able to meaningfully contribute to atmospheric composition in more than a very rough way.
It will be able to nail down reasonably transit shape and depth for many inner system rocky planets, letting us get a good idea of if they are rocky or not, when combined with their mass.

But it has no spectroscope to measure atmospheric absorbtion or occulting system to block out the star to see the planets light.
Even if it did have an occulting system to block the star, it is not sensitive enough to see the planets light. (for other than very close in hot Jupiters)

Spectroscopic followup by ground-based telescopes (or space based, though that is a more limited resource) is needed to get to our current limits.
We need better spectrometers, and more sensitive telescopes in orbit in order to be able to really block well the light from the primary and properly characterise the planets residual atmosphere and surface.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: baldusi on 06/08/2019 12:37 pm
My understanding was that TESS was designed to discover lots of planets by the transition method. All those targets can be studied later by different telescopes. Once you know where and when to look for the transition, you can budget very specific windows on the required telescopes that do have the required spectroscope (and sensitivity). You can also use the wobble method to know the mass, if I'm not mistaken.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hungry4info3 on 06/09/2019 12:27 am
Because TESS targets are systematically brighter than Kepler targets, there will be many small planets discovered around V < 10 stars, and consequently there are many new targets for atmospheric characterization. As a result, TESS is vital for the effort to characterize the atmospheres of low-mass planets, because it will be finding the best targets for it.

Kempton, et al. (2018) (https://arxiv.org/abs/1805.03671) outlined a way to prioritize transiting planets for transmission spectroscopy via a "transmission spectroscopy metric" roughly equal to the Signal-to-Noise ratio for JWST's NIRspec instrument. I've produced a list here showing the planets with the highest 'TSM' so far within the range 0.7 RE < Rp < 1.5 RE. Notice the top of the list is dominated by M dwarf systems from a few ground-based surveys, but TESS, despite its relatively recent arrival on-scene, is already providing great targets for transmission spectroscopy follow-up.

Planet_____Temp__TSM___Discoverer
TRAPPIST-1b400 K43.309TRAPPIST
TRAPPIST-1d288 K36.519TRAPPIST
GJ 1132 b  580 K34.154MEarth
LHS 1140 c 438 K33.389MEarth+HARPS+Spitzer
TRAPPIST-1c342 K30.341TRAPPIST
L 98-59 c  512 K29.660TESS
GJ 357 b   531 K29.331TESS
TRAPPIST-1f219 K20.969Spitzer
TRAPPIST-1g199 K20.454Spitzer
TRAPPIST-1e251 K19.173Spitzer
L 98-59 d  405 K18.862TESS
TRAPPIST-1h169 K18.431Spitzer+K2
L 98-59 b  603 K18.262TESS
GJ 143 c   703 K16.619TESS
K2-229 b   1960 K4.49K2
Kepler-42 c729 K3.921Kepler
Kepler-10 b2169 K3.256Kepler

From the paper:
Quote
Based on the catalog of simulated TESS detections by Sullivan et al. (2015), we determine appropriate cutoff values of the metrics, such that the TESS mission will ultimately yield a sample of ∼300 high-quality atmospheric characterization targets across a range of planet size bins, extending down to Earth-size, potentially habitable worlds.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 06/30/2019 09:40 pm
TESS Finds Its Smallest Planet Yet (https://exoplanets.nasa.gov/news/1587/tess-finds-its-smallest-planet-yet/)

NASA’s Transiting Exoplanet Survey Satellite (TESS) has discovered a world between the sizes of Mars and Earth orbiting a bright, cool, nearby star. The planet, called L 98-59b, marks the tiniest discovered by TESS to date.

Two other worlds orbit the same star. While all three planets’ sizes are known, further study with other telescopes will be needed to determine if they have atmospheres and, if so, which gases are present. The L 98-59 worlds nearly double the number of small exoplanets — that is, planets beyond our solar system — that have the best potential for this kind of follow-up.

“The discovery is a great engineering and scientific accomplishment for TESS,” said Veselin Kostov, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the SETI Institute in Mountain View, California. “For atmospheric studies of small planets, you need short orbits around bright stars, but such planets are difficult to detect. This system has the potential for fascinating future studies.”

A paper on the findings, led by Kostov, was published in the June 27 issue of The Astronomical Journal and is now available online.

https://youtu.be/6wkNlv5nDLE

L 98-59b is around 80% Earth’s size and about 10% smaller than the previous record holder discovered by TESS. Its host star, L 98-59, is an M dwarf about one-third the mass of the Sun and lies about 35 light-years away in the southern constellation Volans. While L 98-59b is a record for TESS, even smaller planets have been discovered in data collected by NASA’s Kepler satellite, including Kepler-37b, which is only 20% larger than the Moon.

The two other worlds in the system, L 98-59c and L 98-59d, are respectively around 1.4 and 1.6 times Earth’s size. All three were discovered by TESS using transits, periodic dips in the star’s brightness caused when each planet passes in front of it.

TESS monitors one 24-by-96-degree region of the sky, called a sector, for 27 days at a time. When the satellite finishes its first year of observations in July, the L 98-59 system will have appeared in seven of the 13 sectors that make up the southern sky. Kostov’s team hopes this will allow scientists to refine what’s known about the three confirmed planets and search for additional worlds.

“If you have more than one planet orbiting in a system, they can gravitationally interact with each other,” said Jonathan Brande, a co-author and astrophysicist at Goddard and the University of Maryland, College Park. “TESS will observe L 98-59 in enough sectors that it may be able to detect planets with orbits around 100 days. But if we get really lucky, we might see the gravitational effects of undiscovered planets on the ones we currently know.”

M dwarfs like L 98-59 account for three-quarters of our Milky Way galaxy’s stellar population. But they are no larger than about half the Sun’s mass and are much cooler, with surface temperatures less than 70% of the Sun’s. Other examples include TRAPPIST-1, which hosts a system of seven Earth-size planets, and Proxima Centauri, our nearest stellar neighbor, which has one confirmed planet. Because these small, cool stars are so common, scientists want to learn more about the planetary systems that form around them.

L 98-59b, the innermost world, orbits every 2.25 days, staying so close to the star it receives as much as 22 times the amount of energy Earth receives from the Sun. The middle planet, L 98-59c, orbits every 3.7 days and experiences about 11 times as much radiation as Earth. L 98-59d, the farthest planet identified in the system so far, orbits every 7.5 days and is blasted with around four times the radiant energy as Earth.

None of the planets lie within the star’s “habitable zone,” the range of distances from the star where liquid water could exist on their surfaces. However, all of them occupy what scientists call the Venus zone, a range of stellar distances where a planet with an initial Earth-like atmosphere could experience a runaway greenhouse effect that transforms it into a Venus-like atmosphere. Based on its size, the third planet could be either a Venus-like rocky world or one more like Neptune, with a small, rocky core cocooned beneath a deep atmosphere.

One of TESS’s goals is to build a catalog of small, rocky planets on short orbits around very bright, nearby stars for atmospheric study by NASA's upcoming James Webb Space Telescope. Four of the TRAPPIST-1 worlds are prime candidates, and Kostov’s team suggests the L 98-59 planets are as well.

The TESS mission feeds our desire to understand where we came from and whether we’re alone in the universe.

"If we viewed the Sun from L 98-59, transits by Earth and Venus would lead us to think the planets are almost identical, but we know they’re not,” said Joshua Schlieder, a co-author and an astrophysicist at Goddard. “We still have many questions about why Earth became habitable and Venus did not. If we can find and study similar examples around other stars, like L 98-59, we can potentially unlock some of those secrets.”
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/16/2019 06:36 pm
Quote
Because it’s looking at bright stars, this means it’s looking for the most part at nearby stars. An exoplanet it just found fits that bill: At just over 22 light years distant, it’s the second nearest transiting exoplanet seen*, and the closest to the Sun detected so far orbiting a tiny red dwarf!

But this story just gets better. The star is part of a triple system of red dwarfs.

Quote
But we do know more about it. Observations using an instrument called HARPS were used to determine the mass of the planet, and it turns out to have at most 8.4 times Earth’s mass. A statistical analysis found a likely mass of 2.2 times Earth’s. That’s interesting, because that means it would have a density of about 90% Earth… which in turn means it’s made of slightly, but only slightly, less heavy stuff. Maybe it has a smaller iron core, or less rock and more water in the mantle and crust. These numbers are iffy, so this is just speculation. But it seems likely it’s a terrestrial planet, with at least a passing resemblance to Venus and Earth. Given the surface temperature, more like the former than the latter.

https://www.syfy.com/syfywire/tess-finds-a-super-earth-orbiting-a-star-in-a-nearby-triple-red-dwarf-star-system
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/18/2019 07:11 am
Quote
But in recently published research, a team of astronomers at The Ohio State University showed that the survey, nicknamed TESS, could also be used to monitor a particular type of supernova, giving scientists more clues about what causes white dwarf stars to explode—and about the elements those explosions leave behind.

"We have known for years that these stars explode, but we have terrible ideas of why they explode," said Patrick Vallely, lead author of the study and an Ohio State astronomy graduate student. "The big thing here is that we are able to show that this supernova isn't consistent with having a white dwarf (take mass) directly from a standard star companion and explode into it—the kind of standard idea that had led to people trying to find hydrogen signatures in the first place. That is, because the TESS light curve doesn't show any evidence of the explosion slamming into the surface of a companion, and because the hydrogen signatures in the SALT spectra don't evolve like the other elements, we can rule out that standard model."

https://m.phys.org/news/2019-07-supernova-kind-nasa-satellite.html
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jacqmans on 07/25/2019 02:44 pm
Northrop Grumman-Built TESS Discovers More than Twenty New Planets after One Year of Exploration

Spacecraft exceeds expectations as it continues to discover new worlds outside of the solar system

DULLES, Va. – July 25, 2019 – Northrop Grumman Corporation (NYSE: NOC) celebrated one year of successful science operations for NASA’s Transiting Exoplanet Survey Satellite (TESS), built and operated by the company for NASA. In just one year, the observatory has discovered more than twenty confirmed planets and identified hundreds of additional candidates for further study in the Southern Hemisphere. TESS will now continue its mission by performing similar observations in the Northern Hemisphere.

Northrop Grumman-Built Tess Discovers More than Twenty New Planets after One Year of Exploration
NASA’s Transiting Exoplanet Survey Satellite (TESS) was built at Northrop Grumman’s Dulles, facility.
“The TESS observatory is exceeding expectations after just one year scanning the skies,” said Steve Krein, vice president, civil and commercial satellites, Northrop Grumman. “As the provider of mission operations for the spacecraft, Northrop Grumman is proud to support this historic mission as it continues to expand our knowledge of the universe while demonstrating our legacy of flight proven scientific spacecraft.”

As the first-ever satellite to perform an exoplanet survey of nearly the entire sky, TESS’s mission, using four wide-field cameras, is to identify planets ranging from Earth-sized to Jupiter-sized, orbiting a wide range of stellar types at various orbital distances. TESS began scanning the skies for new planets July 16, 2018, nearly three months after its successful April 18 launch from Cape Canaveral Air Force Station in Florida.

The TESS satellite was designed, manufactured and tested by Northrop Grumman at the company’s satellite manufacturing facility in Dulles. The company is also responsible for handling mission operations for the observatory. After launch, the observatory went through several tests and began preparation for a series of in-space maneuvers, including a lunar gravity assist, to reach its targeted high-Earth orbit. This lunar flyby was executed May 17, 2018 and the final period-adjustment maneuver was performed May 29.         

The mission team recently announced the discovery of yet another planet, between the sizes of Mars and Earth. The planet, called L 98-59b, marks the tiniest discovered by TESS to date. L 98-59b is around 80 percent Earth’s size. Its host star, L 98-59, is an M dwarf about one-third the mass of the sun and lies about 35 light-years away.

TESS is based on Northrop Grumman’s LEOStar-2™ bus, a flight-proven and flexible satellite platform that accommodates a wide variety of missions. The company has several other satellites in production for upcoming NASA missions including Landsat-9 and the JPSS-2, -3 and -4 weather spacecraft which use the larger LEOStar-3™ bus.

TESS is a NASA astrophysics explorer mission led by the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners besides Northrop Grumman include NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian center for astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory in Lexington, Massachusetts; and the Space Telescope Science Institute in Baltimore, Maryland. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/29/2019 07:24 pm
Quote
Three newly discovered exoplanets could help researchers redefine the shaky line between rocky and gaseous planets, according to new observations from NASA’s Transiting Exoplanet Survey Satellite (TESS). TESS, which marks its first year of operations this month, spotted the trio of planets some 73 light-years away from Earth. The exoplanets are of a type that does not exist in our solar system, being between the Earth and Neptune in size.

That makes the closely packed system, known as TOI-270, a good bet for answering long-standing questions about how such “super-Earths” or “mini-Neptunes” form. The system is within range of ground-based telescopes and soon-to-be-launched orbiting instruments such as NASA’s James Webb Space Telescope (JWST). “This will be one of the key systems for JWST to study,” says Michaël Gillon of the University of Liège in Belgium, who is following up on the TESS discovery.

https://www.sciencemag.org/news/2019/07/newly-discovered-exoplanet-trio-could-unravel-mysteries-super-earth-formation
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 07/31/2019 07:22 pm
Confirmation of Toasty TESS Planet Leads to Surprising Find of Promising World

A piping hot planet discovered by NASA’s Transiting Exoplanet Survey Satellite (TESS) has pointed the way to additional worlds orbiting the same star, one of which is located in the star’s habitable zone. If made of rock, this planet may be around twice Earth’s size.

The new worlds orbit a star named GJ 357, an M-type dwarf about one-third the Sun’s mass and size and about 40% cooler that our star. The system is located 31 light-years away in the constellation Hydra. In February, TESS cameras caught the star dimming slightly every 3.9 days, revealing the presence of a transiting exoplanet — a world beyond our solar system — that passes across the face of its star during every orbit and briefly dims the star’s light.

https://youtu.be/6bWra2Wvudk

“In a way, these planets were hiding in measurements made at numerous observatories over many years,” said Rafael Luque, a doctoral student at the Institute of Astrophysics of the Canary Islands (IAC) on Tenerife who led the discovery team. “It took TESS to point us to an interesting star where we could uncover them.”

The transits TESS observed belong to GJ 357 b, a planet about 22% larger than Earth. It orbits 11 times closer to its star than Mercury does our Sun. This gives it an equilibrium temperature — calculated without accounting for the additional warming effects of a possible atmosphere — of around 490 degrees Fahrenheit (254 degrees Celsius).

“We describe GJ 357 b as a ‘hot Earth,’” explains co-author Enric Pallé, an astrophysicist at the IAC and Luque’s doctoral supervisor. “Although it cannot host life, it is noteworthy as the third-nearest transiting exoplanet known to date and one of the best rocky planets we have for measuring the composition of any atmosphere it may possess.”

But while researchers were looking at ground-based data to confirm the existence of the hot Earth, they uncovered two additional worlds. The farthest-known planet, named GJ 357 d, is especially intriguing.

“GJ 357 d is located within the outer edge of its star’s habitable zone, where it receives about the same amount of stellar energy from its star as Mars does from the Sun,” said co-author Diana Kossakowski at the Max Planck Institute for Astronomy in Heidelberg, Germany. “If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”

Without an atmosphere, it has an equilibrium temperature of -64 F (-53 C), which would make the planet seem more glacial than habitable. The planet weighs at least 6.1 times Earth’s mass, and orbits the star every 55.7 days at a range about 20% of Earth’s distance from the Sun. The planet’s size and composition are unknown, but a rocky world with this mass would range from about one to two times Earth’s size.

Even through TESS monitored the star for about a month, Luque’s team predicts any transit would have occurred outside the TESS observing window.

GJ 357 c, the middle planet, has a mass at least 3.4 times Earth’s, orbits the star every 9.1 days at a distance a bit more than twice that of the transiting planet, and has an equilibrium temperature around 260 F (127 C). TESS did not observe transits from this planet, which suggests its orbit is slightly tilted — perhaps by less than 1 degree — relative to the hot Earth’s orbit, so it never passes across the star from our perspective.

To confirm the presence of GJ 357 b and discover its neighbors, Luque and his colleagues turned to existing ground-based measurements of the star’s radial velocity, or the speed of its motion along our line of sight. An orbiting planet produces a gravitational tug on its star, which results in a small reflex motion that astronomers can detect through tiny color changes in the starlight. Astronomers have searched for planets around bright stars using radial velocity data for decades, and they often make these lengthy, precise observations publicly available for use by other astronomers.

Luque’s team examined ground-based data stretching back to 1998 from the European Southern Observatory and the Las Campanas Observatory in Chile, the W.M. Keck Observatory in Hawaii, and the Calar Alto Observatory in Spain, among many others.

A paper describing the findings was published on Wednesday, July 31, in the journal Astronomy &amp; Astrophysics and is available online.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Jeff Lerner on 08/04/2019 03:58 pm
Confirmation of Toasty TESS Planet Leads to Surprising Find of Promising World

“If the planet has a dense atmosphere, which will take future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface.”


I find these discoveries fascinating....I want to believe we’re going to
Find an exoplanet with water sooner or later.

When they say, “future studies to determine, it could trap enough heat to warm the planet and allow liquid water on its surface., what technology do we have now that will allow us to confirm a dense atmosphere and/or water on an exoplanet ??
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Hungry4info3 on 08/04/2019 05:04 pm
what technology do we have now that will allow us to confirm a dense atmosphere and/or water on an exoplanet ??
For this planet, none.

Assuming GJ 357 d does not transit, the only way we could characterize its atmosphere would be through some direct imaging spectroscopy. The HZ's of M dwarf systems tend to be rather close to their stars, making direct-imaging characterization of such worlds rather challenging, even to the upcoming generation of Extremely Large Telescopes that might be able to do this sort of thing.

If GJ 357 d does transit then there's the option for transmission spectroscopy -- measuring changes in the observed stellar spectrum caused by starlight filtering through the planet's atmosphere. The problem is that the signal-to-noise ratios of such measurements is not expected to be high enough to confidently detect an Earth-like atmosphere with even the upcoming JWST. The best transiting planets for such work would be in the TRAPPIST-1 system, and it's a bit of an open question whether or not the amount of time required on JWST would be worth allocating to it (i.e., observing dozens to hundreds of transits). When you start getting colder planets like GJ 357, the atmospheric scale height tends to be rather low, further challenging these sorts of observations.

Finally, there's a rather major problem with GJ 357 d in particular that really should have rendered any sensationalist headlines about its potential habitability rather moot. The planet's minimum mass is ~6 ME. With the exception of short-period planets whose density is increased due to photoevaporation, planets of this mass seem to always turn out to be more Neptune-like in their composition than Earth-like. These planets are not terrestrial planets. They probably don't have a solid surface. GJ 357 d is not a promising habitable planet candidate.

Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 11/06/2019 10:56 pm
"Dive Into TESS's Southern Sky Panorama"
https://www.youtube.com/watch?v=P3KevBr4go4
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: redliox on 11/07/2019 03:36 am
Although TESS is meant for relatively close stars, the fact it's sky map had the Large Magellanic Cloud under the constant observation zone in the middle felt like an opportunity.  Would TESS be able to notice much about it, given the time concentrated viewing the area?
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 12/11/2019 06:39 am
We report on initial results from 20 days' worth of Transiting Exoplanet Survey Satellite spacecraft observations of comet 46P/Wirtanen. The long-duration, high-cadence measurements show a 2018 September 26 outburst that exhibited a two-phase, 0.5 mag brightening profile, and may be the best temporally characterized natural outburst ever recorded. Gas velocities from the outburst peaked at 800 ${\rm{m}}\,{{\rm{s}}}^{-1}$, while dust expanded at only 10s of ${\rm{m}}\,{{\rm{s}}}^{-1}$. Coadded images also revealed a previously unreported dust trail that extends beyond the 24° field of view.

https://iopscience.iop.org/article/10.3847/2041-8213/ab564d

NASA’s Exoplanet-Hunting Mission Catches a Natural Comet Outburst in Unprecedented Detail

Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS), astronomers at the University of Maryland (UMD), in College Park, Maryland, have captured a clear start-to-finish image sequence of an explosive emission of dust, ice and gases during the close approach of comet 46P/Wirtanen in late 2018. This is the most complete and detailed observation to date of the formation and dissipation of a naturally-occurring comet outburst. The team members reported their results in the November 22 issue of The Astrophysical Journal Letters.

https://www.nasa.gov/feature/goddard/2019/nasa-s-exoplanet-hunting-mission-catches-a-natural-comet-outburst-in-unprecedented-detail
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: ncb1397 on 01/07/2020 02:25 am
First earth sized planet in habitable zone:

Quote
NASA's Transiting Exoplanet Survey Satellite (TESS) has discovered its first Earth-size planet in its star's habitable zone, the range of distances where conditions may be just right to allow the presence of liquid water on the surface. Scientists confirmed the find, called TOI 700 d, using NASA's Spitzer Space Telescope and have modeled the planet's potential environments to help inform future observations.
https://www.jpl.nasa.gov/news/news.php?feature=7569

https://www.youtube.com/watch?v=QU0qsIGS6MQ

Just need to get JWST up there now...
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 01/07/2020 07:14 am
From Event Horizon TOI 700 d TESS’s First Earth-sized Habitable-Zone Planet with Dr. Joey Rodriguez & Dr. Andrew Vanderburg:

https://youtu.be/uVGGS2xUAks
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: bolun on 01/16/2020 09:18 am
Meet the NASA intern who discovered a new planet on his third day

https://www.bbc.com/news/newsbeat-51122019
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: redliox on 08/12/2020 04:18 pm
TESS has begun its extended mission, focusing on the Southern Hemisphere but also more on the ecliptic.

I seem to remember there had been numerous options for missions extensions considered but can't recall the details.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Zed_Noir on 08/12/2020 05:37 pm
TESS has begun its extended mission, focusing on the Southern Hemisphere but also more on the ecliptic.

I seem to remember there had been numerous options for missions extensions considered but can't recall the details.

IIRC, the Falcon 9 lofted TESS into a better than expected orbit. So have more propellants to extended the mission by many years. Which give the mission planners more options then originally planned. Presuming the CCD detectors remains functional.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Nomadd on 08/12/2020 05:55 pm
 There's a question I had at the beginning I can't find the answer to. Will they be targeting some of Kepler's discoveries to compare results between the two? It seems like the extra data might help reduce the SNR, or whatever they call the optical version, for both.
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 08/12/2020 06:35 pm
TESS Completes its Primary Mission:

https://youtu.be/uOxuTLPAlzI
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: jebbo on 08/12/2020 07:37 pm
There's a question I had at the beginning I can't find the answer to. Will they be targeting some of Kepler's discoveries to compare results between the two? It seems like the extra data might help reduce the SNR, or whatever they call the optical version, for both.

Yes, pretty sure TESS re-observed the Kepler field in year 2 though I don't think I've seen any published results yet.

Edit: sectors 14 & 15

Because Kepler was looking at fainter stars and TESS is looking at brighter ones, there are only a few hundred which can really be looked at by both. This paper looks examines what more this will tell us: https://arxiv.org/abs/1810.02826

--- Tony
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 09/16/2020 05:02 pm
Potential Giant World Circling Tiny Star:

https://youtu.be/fDhG0ppvQ2g
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 10/06/2020 04:24 pm
TESS’s Northern Sky Vista:

https://youtu.be/aKSvBJz_CdU

Its primary mission is now complete & it swaps back to the Southern Sky for its extended mission.
Title: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 03/29/2021 08:59 am
The TESS Objects of Interest Catalog from the TESS Prime Mission

We present 2,241 exoplanet candidates identified with data from the Transiting Exoplanet Survey Satellite (TESS) during its two-year prime mission. We list these candidates in the TESS Objects of Interest (TOI) Catalog, which includes both new planet candidates found by TESS and previously-known planets recovered by TESS observations. We describe the process used to identify TOIs and investigate the characteristics of the new planet candidates, and discuss some notable TESS planet discoveries. The TOI Catalog includes an unprecedented number of small planet candidates around nearby bright stars, which are well-suited for detailed follow-up observations. The TESS data products for the Prime Mission (Sectors 1-26), including the TOI Catalog, light curves, full-frame images, and target pixel files, are publicly available on the Mikulski Archive for Space Telescopes.

https://arxiv.org/abs/2103.12538
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 06/22/2021 04:25 pm
Two new gaseous planets found by citizen scientists

Quote
Two new gaseous planets have been found orbiting a sun-like star 352 light-years from Earth -- and citizen scientists helped discover them while collaborating with astronomers.

The two exoplanets, which are planets that orbit stars outside of our solar system, are called planet b and planet c. They orbit a star known as HD 152843, which has a similar mass to our sun but is 1.5 times bigger and brighter.

Quote
Citizen scientists were able to help discover these planets by participating in Planet Hunters TESS. This NASA-funded project, available on the Zooniverse website, includes more than 29,000 people around the globe. It allows people to help search for exoplanets using data from NASA's Transiting Exoplanet Survey Satellite, or TESS mission.

https://edition.cnn.com/2021/06/22/world/exoplanets-nasa-citizen-science-scn/index.html
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: bolun on 07/14/2021 03:43 pm
NASA’s TESS Discovers Stellar Siblings Host ‘Teenage’ Exoplanets (https://www.nasa.gov/feature/goddard/2021/nasa-s-tess-discovers-stellar-siblings-host-teenage-exoplanets)

Quote
Thanks to data from NASA’s Transiting Exoplanet Survey Satellite (TESS), an international collaboration of astronomers has identified four exoplanets, worlds beyond our solar system, orbiting a pair of related young stars called TOI 2076 and TOI 1807.

Quote
TOI 2076 and TOI 1807 reside over 130 light-years away with some 30 light-years between them, which places the stars in the northern constellations of Boötes and Canes Venatici, respectively. Both are K-type stars, dwarf stars more orange than our Sun, and around 200 million years old, or less than 5% of the Sun’s age. In 2017, using data from ESA’s (the European Space Agency’s) Gaia satellite, scientists showed that the stars are traveling through space in the same direction.

Astronomers think the stars are too far apart to be orbiting each other, but their shared motion suggests they are related, born from the same cloud of gas.

https://youtu.be/RE-NpbAW3lM
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 08/04/2021 09:24 pm
TESS Maps Red Giants Across the Sky

https://youtu.be/uZaRnyN0wp0
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 08/04/2021 09:26 pm
TESS Tracks a Giant’s Pulsations

https://youtu.be/jrI-7COKnic
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 08/04/2021 09:27 pm
Tuning Into a Trio of Red Giants

https://youtu.be/MRXC12BFStI
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 08/31/2021 05:04 pm
Populating the brown dwarf and stellar boundary: Five stars with transiting companions near the hydrogen-burning mass limit

We report the discovery of five transiting companions near the hydrogen-burning mass limit in close orbits around main sequence stars originally identified by the Transiting Exoplanet Survey Satellite (TESS) as TESS Objects of Interest (TOIs): TOI-148, TOI-587, TOI-681, TOI-746, and TOI-1213. Using TESS and ground-based photometry as well as radial velocities from the CORALIE, CHIRON, TRES, and FEROS spectrographs, we found the companions have orbital periods between 4.8 and 27.2 days, masses between 77 and 98 MJup, and radii between 0.81 and 1.66 RJup. These targets have masses near the uncertain lower limit of hydrogen core fusion (∼73-96 MJup), which separates brown dwarfs and low-mass stars. We constrained young ages for TOI-587 (0.2 ± 0.1 Gyr) and TOI-681 (0.17 ± 0.03 Gyr) and found them to have relatively larger radii compared to other transiting companions of a similar mass. Conversely we estimated older ages for TOI-148 and TOI-746 and found them to have relatively smaller companion radii. With an effective temperature of 9800 ± 200 K, TOI-587 is the hottest known main-sequence star to host a transiting brown dwarf or very low-mass star. We found evidence of spin-orbit synchronization for TOI-148 and TOI-746 as well as tidal circularization for TOI-148. These companions add to the population of brown dwarfs and very low-mass stars with well measured parameters ideal to test formation models of these rare objects, the origin of the brown dwarf desert, and the distinction between brown dwarfs and hydrogen-burning main sequence stars.

https://arxiv.org/abs/2107.03480
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 10/19/2021 03:39 pm
An accreting white dwarf displaying fast transitional mode switching

Abstract
Accreting white dwarfs are often found in close binary systems with orbital periods ranging from tens of minutes to several hours. In most cases, the accretion process is relatively steady, with significant modulations only occurring on timescales of ~days or longer1,2. Here we report the discovery of abrupt drops in the optical luminosity of the accreting white dwarf binary system TW Pictoris by factors up to 3.5 on timescales as short as 30 minutes. The optical light curve of this binary system obtained by the Transiting Exoplanet Survey Satellite (TESS) clearly displays fast switches between two distinct intensity modes that probably track the changing mass accretion rate onto the white dwarf. In the low mode, the system also displays magnetically gated accretion bursts3,4,5, which implies that a weak magnetic field of the white dwarf truncates the inner disc at the co-rotation radius in this mode. The properties of the mode switching observed in TW Pictoris appear analogous to those observed in transitional millisecond pulsars6,7,8,9,10, where similar transitions occur, although on timescales of ~tens of seconds. Our discovery establishes a previously unrecognized phenomenon in accreting white dwarfs and suggests a tight link to the physics governing magnetic accretion onto neutron stars.

https://www.nature.com/articles/s41550-021-01494-x

Source: https://phys.org/news/2021-10-astronomers-white-dwarf.amp
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 11/11/2021 04:40 pm
TOI-2257 b: A highly eccentric long-period sub-Neptune transiting a nearby M dwarf

Thanks to the relative ease of finding and characterizing small planets around M dwarf stars, these objects have become cornerstones in the field of exoplanet studies. The current paucity of planets in long-period orbits around M dwarfs make such objects particularly compelling as they provide clues about the formation and evolution of these systems. In this study, we present the discovery of TOI-2257 b (TIC 198485881), a long-period (35 d) sub-Neptune orbiting an M3 star at 57.8pc. Its transit depth is about 0.4%, large enough to be detected with medium-size, ground-based telescopes. The long transit duration suggests the planet is in a highly eccentric orbit (e∼0.5), which would make it the most eccentric planet that is known to be transiting an M-dwarf star. We combined TESS and ground-based data obtained with the 1.0-m SAINT-EX, 0.60-m TRAPPIST-North and 1.2-m FLWO telescopes to find a planetary size of 2.2 R⊕ and an orbital period of 35.19 days. In addition, we make use of archival data, high-resolution imaging, and vetting packages to support our planetary interpretation. With its long period and high eccentricity, TOI-2257 b falls in a novel slice of parameter space. Despite the planet's low equilibrium temperature (∼ 256 K), its host star's small size (R∗=0.311±0.015) and relative infrared brightness (Kmag = 10.7) make it a suitable candidate for atmospheric exploration via transmission spectroscopy.

https://arxiv.org/abs/2111.01749

Source:

https://phys.org/news/2021-11-astronomers-sub-neptune-exoplanet-orbiting-nearby.html
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 11/18/2021 07:40 am
This study re-confirms that Proxima b does not transit it’s host Star from our viewpoint, and in fact no transits at all were discovered in the data for any other planet that may exist in the system larger than the size of Mars.

No Transits of Proxima Centauri Planets in High-Cadence TESS Data

Proxima Centauri is our nearest stellar neighbor and one of the most well-studied stars in the sky. In 2016, a planetary companion was detected through radial velocity measurements. Proxima Centauri b has a minimum mass of 1.3 Earth masses and orbits with a period of 11.2 days at 0.05 AU from its stellar host, and resides within the star's Habitable Zone. While recent work has shown that Proxima Centauri b likely does not transit, given the value of potential atmospheric observations via transmission spectroscopy of the closest possible Habitable Zone planet, we reevaluate the possibility that Proxima Centauri b is a transiting exoplanet using data from the Transiting Exoplanet Survey Satellite (TESS). We use three sectors (Sectors 11, 12, and 38 at 2-minute cadence) of observations from TESS to search for planets. Proxima Centauri is an extremely active M5.5 star, emitting frequent white-light flares; we employ a novel method that includes modeling the stellar activity in our planet search algorithm. We do not detect any planet signals. We injected synthetic transiting planets into the TESS and use this analysis to show that Proxima Centauri b cannot be a transiting exoplanet with a radius larger than 0.4 R⊕. Moreover, we show that it is unlikely that any Habitable Zone planets larger than Mars transit Proxima Centauri.

https://arxiv.org/abs/2110.10702
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 12/20/2021 09:26 am
TESS has found a new representative of the brown dwarf desert

09:59 Dec 20 2021

The TESS space telescope has found a new massive brown dwarf, whose properties place it in an underexplored area - the brown dwarf desert. Scientists hope that further investigation of this object will help to understand exactly how such sub-stellar bodies are formed. A preprint of the work is available on the ArXiv.org website.

If you look at the properties of brown dwarfs, which are considered intermediate objects between stars and giant planets, you can notice the lack of bodies with a mass of 35-55 Jupiter masses, located less than three astronomical units from the parent stars of the main sequence. This phenomenon is called the desert of brown dwarfs, and it may be associated with different mechanisms for the formation of brown dwarf companions with low and high mass. In addition, this may be due to the peculiarities of the dynamic interaction of brown dwarfs of different masses with their stars. However, so far, scientists do not have enough observational data for such objects to understand their origin.

A group of astronomers led by Caleb I. Cañas from the University of Pennsylvania reports the discovery of a new massive brown dwarf TOI-2119.01, which has become another representative of the brown dwarf desert. It was originally found by the TESS space telescope using the transit method, and later the discovery was confirmed using ground-based telescopes.

The mass of the parent star, which became the red dwarf, is 0.53 solar masses, and the radius is 0.51 solar radius. The  brown dwarf has a brightness temperature of 2,100 Kelvin and a mass of 67 Jupiter masses. It has been classified as an early L-type dwarf with a radius of 1.11 that of Jupiter. The orbit of TOI-2119.01 is highly elongated (eccentricity 0.3362), the dwarf makes one revolution around the star in just 7.2 Earth days, and one revolution around its axis - in 13.2 days.

The age of the dwarf has been estimated at 0.7-5.1 billion years, while evolutionary models of brown dwarfs usually consider a period of less than one billion years of life for such objects. Due to the fact that the exact age of TOI-2119.0 is still difficult to establish, it is ill-suited for imposing a constraint on theoretical models, so observations will continue. In addition, there may be a third body in the system, but this is yet to be verified.

Earlier, we talked about how the minimum mass for burning lithium in brown dwarfs did not fit into the model.

Alexander Voytyuk

https://nplus1.ru/news/2021/12/20/brown-dwarf-m-dwarf
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Star One on 01/26/2022 04:33 pm
Quote
NASA’s Transiting Exoplanet Survey Satellite has now identified more than 5,000 possible exoplanet candidates – TESS Objects of Interest, or TOIs – mostly from a faint star search led by Michelle Kunimo, a postdoc at MIT. While TOIs are, by definition, unconfirmed, astronomers are confident additional observations will add to TESS’s list of known exoplanets.

“This time last year, TESS had found just over 2,400 TOIs. Today, TESS has reached more than twice that number — a huge testament to the mission and all the teams scouring the data for new planets. I’m excited to see thousands more in the years to come!”

Quote
It will take additional observations by astronomers around the world to confirm whether a TOI is, in fact, an actual exoplanet. Three such confirmations were announced at the American Astronomical Society’s winter meeting earlier this month.

A team led by Samuel Grunblatt, a postdoctoral fellow at the American Museum of Natural History and the Flatiron Institute in New York City, found three gas giants in TOI data. The planets have some of the shortest-period orbits around subgiant or giant stars yet found and one of them, TOI-2337b, likely will be consumed by its host star in less than a million years.

https://astronomynow.com/2022/01/24/astronomers-mining-an-increasingly-rich-trove-of-tess-exoplanet-data/
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: redliox on 02/05/2022 09:09 pm
For the extended mission happening now, what kind of plan is TESS following?  There were several options ranging from repeating the prior pattern to scanning thin strips of the sky intensely.  Any specifics on where it's pointing itself now?
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Yiosie on 02/06/2022 12:28 am
For the extended mission happening now, what kind of plan is TESS following?  There were several options ranging from repeating the prior pattern to scanning thin strips of the sky intensely.  Any specifics on where it's pointing itself now?

The observing strategy and timeline for the current extended mission is listed here:

https://heasarc.gsfc.nasa.gov/docs/tess/extended.html

TESS is currently observing "Sector 48" at "an ecliptic latitude of +54°."
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 02/11/2022 03:11 pm
TESS has found a hot super-Earth around a very close red dwarf

09:55 11 Feb. 2022

The TESS space telescope has discovered a new hot super-Earth, which is located in a red dwarf system very close to the Sun. Further studies of this object can help astronomers understand the origin of the sub-Neptune desert - the lack of planets close to stars with masses of 1.4-2 Earth masses. The preprint of the work is published on the website arXiv.org.

One of the problems in exoplanetology has become the nature of the sub-Neptune desert . This is the name given to the observed lack of planets with masses of 1.4-2 Earth masses that are close to their stars, which separates super-Earths and mini-Neptunes. It is still unclear exactly what mechanisms lead to the formation of these types of planets and why the desert phenomenon occurs. Perhaps rocky super-Earths are born as a result of photoevaporation of the outer shells of mini-neptunes rich in hydrogen, or another mechanism for the loss of mass of the atmosphere. To understand this, scientists need to increase the sample of known exoplanets of these types and determine their parameters with great accuracy.

A team of astronomers led by Jonas Kemmer from the University of Heidelberg announced the discovery of the exoplanet GJ 3929b in the M-dwarf system, located 51.6 light-years from the Sun. Initially discovered by the TESS space telescope using the transit method, the discovery was subsequently confirmed using the CARMENES, SAINT-EX, LCOGT and OSN ground-based telescopes, which also helped to determine the parameters of the object.

The radius of the planet GJ 3929b was estimated at 1.15 Earth radii, and the mass at 1.21 Earth masses. This gives a bulk density value of 4.4 grams per cubic centimeter, which is comparable to Earth's average density, so the object could be a rocky exoplanet. A year on the planet lasts 2.61 Earth, it is at an average distance from its star of about 0.0026 astronomical units. The equilibrium temperature of GJ 3929b is estimated at 569 kelvin, which means that it belongs to the category of hot super-Earths.

The brightness of the parent star (which is one third smaller than our own) and the size of GJ 3929b make the exoplanet an interesting target for future research with the James Webb Space Telescope, which will be able to find its atmosphere, if any. In addition, there may be another exoplanet in the system with an orbital period of 14.303 days, however this has yet to be confirmed.

Earlier, we talked about how scientists found a hot Neptune in the Neptune Desert, another mysterious feature in a sample of known exoplanets.

Alexander Voytyuk

https://nplus1.ru/news/2022/02/11/tess-hot-super-earth
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 05/01/2022 02:20 am
TESS finds two rocky exoplanets around a red dwarf very close to the Sun

21:32 30 Apr. 2022

Astronomers using ground-based and space telescopes have discovered two rocky exoplanets that are 2-3 times heavier than the Earth near the red dwarf HD 260655 close to the Sun. They are expected to be explored by the James Webb Space Telescope in the future. A preprint of the work is available at arXiv.org.

Dwarf stars of the spectral type M are of particular interest to astronomers - planets with radii from one to four Earth radii are often found around such luminaries, and cases of detection of multiplanetary systems are not uncommon. If we take into account that observations of such stars make it possible to obtain fairly accurate estimates of the mass and radius of exoplanets orbiting them, then it becomes possible to determine how diverse the volumetric compositions of terrestrial exoplanets are and whether they have atmospheres.

A team of astronomers led by Rafael Luque of the University of Chicago announced the discovery of two exoplanets around the bright red dwarf HD 260655, which is 32.6 light-years from the Sun. The discovery was made by the transit method using the TESS space telescope and confirmed by the radial velocity method using the HIRES and CARMENES receivers mounted on ground-based telescopes.

The star has a mass of 0.43 solar masses and a radius of 0.43 solar radii, its age is estimated at 2–8 billion years, and its effective temperature is 3803 kelvin. The closest exoplanet to the star, HD 260655b, has a radius of 1.24 Earth radii and a mass of 2.14 Earth masses. This gives a volume average density of the planet of 6.2 grams per cubic centimeter, slightly more than Earth's average density. A year on HD 260655b lasts 2.77 days, the average distance from the star is estimated at 0.03 astronomical units, and the equilibrium temperature is 709 kelvin.

The exoplanet HD 260655c has a radius of 1.53 Earth radii and a mass of 3.09 Earth masses. The bulk density of the exoplanet is 4.7 grams per cubic centimeter. A year on HD 260655c lasts 5.7 days, the average distance from the star is estimated at 0.047 astronomical units, and the equilibrium temperature is 557 kelvin.

The researchers concluded that HD 260655 is unique in terms of comparative studies of rocky exoplanets. This is the third system closest to the Sun, containing an M-dwarf and several planets that periodically pass across the disk of the star. It is expected that in the future the James Webb Space Telescope will observe the newly discovered objects, which will look for their atmospheres.

Earlier we talked about how astronomers confirmed the existence of an Earth-like planet near Proxima Centauri.

Alexander Voytyuk

https://nplus1.ru/news/2022/04/30/exoplanets-rocky
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 05/30/2022 11:09 am
TESS Finds New Companion Exoplanet Inside Hot Jupiter's Orbit

10:33 30 May 2022

Astronomers using the TESS space telescope have discovered a new exoplanet system in which an exoplanet companion is located inside the orbit of hot Jupiter. WASP-132c is the fourth such object, which does not fit into the high-eccentricity migration scenario that explains the formation of most hot Jupiters. The preprint is available at arXiv.org.

Since the discovery of the first exoplanet around a sun-like star at the end of the last century, objects like hot Jupiters have been one of the great mysteries of exoplanetology. These planets are characterized by radii greater than 8 Earth radii, orbital periods less than 10 days and represent a class of objects that have no analogues in our solar system. Traditional theories cannot explain the existence of gas giants so close to their parent stars, so scientists have developed new scenarios for the formation of such objects, such as migration in the circumstellar disk or the processes of gravitational interaction and scattering of planets. In particular, there is evidence that many of the hot Jupiters originally formed outside the snow line .in the system and then migrated closer to the star. However, none of the currently available scenarios can satisfy all model constraints derived from observational data, so the main pathways for the formation of hot Jupiters are still poorly understood.

One curious property of hot Jupiters that may indicate the path of formation is their uniqueness as planets in their system, although they may have distant companions. This absence of nearby companions is predicted by a high-eccentricity migration formation mechanism. In this case, the planet is transferred to an eccentric orbit due to the snow line under the influence of some gravitational perturbations, and eventually the orbit becomes circular and very close to its star. At the same time, such a mechanism leads to scattering and possible ejection from the system of other planets.

Of the roughly 500 confirmed hot Jupiters to date, only three have been found to be exceptions - WASP-47, Kepler-730 and TOI-1130. In these, hot Jupiters have at least one close planetary mass companion. Thus, the migration scenario with high eccentricity is unlikely; most likely, the systems were formed due to the migration of protoplanets inside the circumstellar disk closer to the star at the stage of their formation.

A team of astronomers led by Benjamin J. Hord of the University of Maryland announced the discovery of the fourth system containing a hot Jupiter and a companion planet close to it. We are talking about the orange dwarf WASP-132, with a mass of 0.78 solar masses, which is located at a distance of about 400 light years from the Sun in the constellation. The system was monitored by the TESS space telescope, which found the companion exoplanet using the transit method, and astronomers also used archival observational data from the CORALIE spectrograph of the ground-based EULER telescope to confirm the discovery.

The TESS data made it possible to refine the parameters of the hot Jupiter WASP-132b, found back in 2016 by the ground-based SuperWASP telescope. This exoplanet has a mass of 0.41 Jupiter masses, a radius of 0.754 Jupiter radii, and an orbital period of 7.13 days. Inside its orbit is the super-Earth WASP-132c, which has a radius of 1.85 Earth radii, an orbital period of 1.01 days and an upper mass limit of 37.35 Earth masses.

Dynamic modeling shows that the system is dynamically stable for a time scale of 100 million years. The scientists note that this discovery suggests that a mechanism other than the high-eccentricity migration scenario may play a significant role in the formation of hot Jupiters, and in the case of WASP-132, further observations are needed to refine exoplanet masses and confirm the discovery of WASP-132c.

Earlier, we talked about how scientists found an ultra-hot Jupiter falling on a star and for the first time recorded radio emission from such a planet.

Alexander Voytyuk

https://nplus1.ru/news/2022/05/30/companion-wasp-132-b
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: Rondaz on 07/22/2022 09:38 am
TESS finds two new warm Jupiters

18:54 21 July 2022

Astronomers have confirmed two new exoplanet discoveries with the TESS space telescope. The telescope found two warm Jupiters orbiting sun-like stars that may have migrated through their systems in the past. A preprint of the work is available at arXiv.org.

Most of the known exogiants found by the transit method are hot Jupiters with periods of revolution around their stars of less than ten days, which are characterized by a high temperature of the outer layers. Due to their proximity to parent stars, their orbits cannot provide enough information about the mechanism of formation of such objects. However, the orbital parameters of exogiants more distant from stars, such as warm Jupiters, are less influenced by the parent star. Their orbital periods are in the range from 10 to 200 days, as in the case of hot Jupiters, if warm Jupiters do not form in the orbits where they are found, then there is a need for a mechanism for the planet to migrate through the system, from the point of formation to the point of detection.

A team of astronomers led by Solène Ulmer-Moll of the Geneva Observatory in Switzerland announced the confirmation of two new discoveries of warm Jupiters, designated NGTS-20b (TOI-5152b) and TOI-5153b. The objects were initially detected by the TESS space telescope using the transit method, later the discoveries were confirmed by the radial velocity method using the CORALIE, FEROS, HARPS, CHIRON and TRES spectrographs installed on ground-based telescopes, and by the transit method using the NGTS (Next Generation) ground-based telescope system. transit survey).

In the case of NGTS-20b, the host star has a mass of 1.47 solar masses, a radius of 1.78 solar radii, and a spectral type of G1. An exoplanet with a mass of 2.98 Jupiter masses and a radius of 1.07 Jupiter radii revolves around it with a period of 54.19 hours. The orbital eccentricity of NGTS-20b is 0.432, and the equilibrium temperature is 688 Kelvin. The age of the system is estimated to be between 1.4 and 6.8 billion years, it is located at a distance of about 1200 light years from the Sun.

The parent star of the planet TOI-5153b is of type F8, has a mass of 1.24 solar masses and a radius of 1.4 solar radii. The exoplanet itself has an orbital period of 20.33 days, a mass of 3.26 Jupiter masses, and a radius of 1.06 Jupiter radii. The orbital eccentricity of the exogiant is 0.091, the equilibrium temperature is 906 kelvin. The age of the system is estimated at 5.4 billion years, and the distance to it is about 1270 light years.

Both exoplanets are enriched in metals, and their abundances of heavy elements are consistent with mass-to-metallicity models for gas giants. It is hypothesized that they may have formed through a high eccentricity migration process or migrated towards the star due to interactions with an undetected companion. Further observations should more accurately determine their nature.

Earlier, we talked about how TESS found two rocky exoplanets around a red dwarf very close to the Sun and an ultra-hot Jupiter falling into a star.

Alexander Voytyuk

https://nplus1.ru/news/2022/07/21/tess-new-exogiants
Title: Re: NASA - Transiting Exoplanet Survey Satellite ( TESS ) updates
Post by: briantipton on 07/22/2022 09:52 am


In the case of NGTS-20b, the host star has a mass of 1.47 solar masses, a radius of 1.78 solar radii, and a spectral type of G1. An exoplanet with a mass of 2.98 Jupiter masses and a radius of 1.07 Jupiter radii revolves around it with a period of 54.19 hours.



That should be 54.19 days, not hours