SpaceX Falcon 9 : TESS : April 18, 2018 : Discussion

[LouScheffer]

This may be Day One of a mission that will give us a first look at an exoplanet that harbours life.

Someday, if and when we develop the technology for interstellar travel, our first destinations may be planets that are discovered by TESS.

I think this is statistically unlikely.  TESS sees only transiting planets, which are a small percentage (around 1% of Earth-like orbits).  So whatever TESS finds, there is likely an equally good candidate(s) that are much closer, but do not transit.   These can be found by other means that are being worked on now, so these closer targets will be known long before there are starships.

[speedevil]

I think this is statistically unlikely.  TESS sees only transiting planets, which are a small percentage (around 1% of Earth-like orbits).  So whatever TESS finds, there is likely an equally good candidate(s) that are much closer, but do not transit.   These can be found by other means that are being worked on now, so these closer targets will be known long before there are starships.

Specifically, GAIA.
Close by stars can have planets round them detected by the small (3000km) variations in their position over the orbit of earth-sized planets.
They 'wobble'.
Also, at some point soon, direct observation of nearby star systems with star-shades in space may be done, which helps lots in being able to detect smaller planets.

[jebbo]

I think this is statistically unlikely.  TESS sees only transiting planets, which are a small percentage (around 1% of Earth-like orbits).  So whatever TESS finds, there is likely an equally good candidate(s) that are much closer, but do not transit.   These can be found by other means that are being worked on now, so these closer targets will be known long before there are starships.

Specifically, GAIA.
Close by stars can have planets round them detected by the small (3000km) variations in their position over the orbit of earth-sized planets.
They 'wobble'.
Also, at some point soon, direct observation of nearby star systems with star-shades in space may be done, which helps lots in being able to detect smaller planets.

Gaia astrometry will not detect Earth-size planets, but will find plenty of Jupiter analogues.
Earth-sized planets will be found using RV ... using instruments like ESPRESSO at the VLT.

[AncientU]

I think this is statistically unlikely.  TESS sees only transiting planets, which are a small percentage (around 1% of Earth-like orbits).  So whatever TESS finds, there is likely an equally good candidate(s) that are much closer, but do not transit.   These can be found by other means that are being worked on now, so these closer targets will be known long before there are starships.

Specifically, GAIA.
Close by stars can have planets round them detected by the small (3000km) variations in their position over the orbit of earth-sized planets.
They 'wobble'.
Also, at some point soon, direct observation of nearby star systems with star-shades in space may be done, which helps lots in being able to detect smaller planets.

Star shade is very promising technology, but the telescope that is needed to do random or blind searches for earth-mass planets is not on the horizon.  JWST will have limited time allocated to spectroscopic searches (a full week at a time?) of very carefully vetted Earth analogues in the habitable zone or their respective stars.  After JWST, it is anyone's guess when the next mega-observatory will be built/launched.

A dedicated, large aperture, cold telescope (4m off-axis parabola, for instance, like HabEX) with one or more dedicated star shades is needed.  WFIRST supposedly will 'demo' the technology, but it is a warm telescope; much of the interesting spectra for detecting/characterizing 'life' is at longer wavelengths than their 2 micron limit.

[Semmel]

I think this is statistically unlikely.  TESS sees only transiting planets, which are a small percentage (around 1% of Earth-like orbits).  So whatever TESS finds, there is likely an equally good candidate(s) that are much closer, but do not transit.   These can be found by other means that are being worked on now, so these closer targets will be known long before there are starships.

Specifically, GAIA.
Close by stars can have planets round them detected by the small (3000km) variations in their position over the orbit of earth-sized planets.
They 'wobble'.
Also, at some point soon, direct observation of nearby star systems with star-shades in space may be done, which helps lots in being able to detect smaller planets.

Star shade is very promising technology, but the telescope that is needed to do random or blind searches for earth-mass planets is not on the horizon.  JWST will have limited time allocated to spectroscopic searches (a full week at a time?) of very carefully vetted Earth analogues in the habitable zone or their respective stars.  After JWST, it is anyone's guess when the next mega-observatory will be built/launched.

A dedicated, large aperture, cold telescope (4m off-axis parabola, for instance, like HabEX) with one or more dedicated star shades is needed.  WFIRST supposedly will 'demo' the technology, but it is a warm telescope; much of the interesting spectra for detecting/characterizing 'life' is at longer wavelengths than their 2 micron limit.

Ill be at the SPIE for astronomical instrumentation in Texas this year. There usually are some sessions on new proposals. (I saw the sunshade proposal there 4 years ago in Montreal). Will keep an eye open for things and report what I see.

[Journeyman]

I have not read anywhere what happened to the fairing recovery? They did attempt this on this flight right?

[e of pi]

I have not read anywhere what happened to the fairing recovery? They did attempt this on this flight right?

No, at this time their only fairing recovery boat is on the west coast.

[Journeyman]

I have not read anywhere what happened to the fairing recovery? They did attempt this on this flight right?

No, at this time their only fairing recovery boat is on the west coast.

Yes I'm aware that the recovery boat is only available for West coast launches. But I remember reading they where going to fly the fairing recovery tech on this one to test it, not recovering it but let it splash softly into the ocean.

Or did I confuse this with another flight?

[pb2000]

I think Hans said that the fairing (half?) had the recovery hardware, but without Mr Steven, the best they could hope for was another soft splashdown.

[Journeyman]

Yeah that was what I remember hearing. Surprised there has been no official updates on that. But maybe they don't bother reporting details when they can't recover it and show it for cameras.

[launchwatcher]

You would think high-profile online content management systems like YouTube would understand that we are smart enough to realize that they're giving results that badly fit the search criteria precedence over results which fit them well.  That can only mean that, 1) their search function sucks rocks, or 2) they are giving some types of providers precedence, even when their result doesn't really fit.  For monetary or other considerations.

There's a not-well-known way to improve the recommendations you get from YouTube.

There's a pop-up menu attached to (some) recommended videos.   The three-dot menu button (some folks call it a "kebab menu" to contrast with the three-line "hamburger menu" icon) shows a menu which includes a "not interested" button.   

If you select "not interested", it gives you an option of "Tell us why".   If you select that, you get a couple options to choose from.
(already watched it, don't like the video, don't like the channel).

This does not immediately blacklist a channel but since discovering this feature I've been making a habit of selecting "not interested" on all the clickbait/flat earther/tinfoil hat crap that turns up and the quality of recommendations I'm getting has gone way up.

[billh]

I noticed this wire in John Kraus's launch photo. I don't recall seeing it before. Any ideas what this is?

[goretexguy]

You would think high-profile online content management systems like YouTube would understand that we are smart enough to realize that they're giving results that badly fit the search criteria precedence over results which fit them well.  That can only mean that, 1) their search function sucks rocks, or 2) they are giving some types of providers precedence, even when their result doesn't really fit.  For monetary or other considerations.

There's a not-well-known way to improve the recommendations you get from YouTube.

I led a team which built a search engine for an online e-commerce concern. We created a feature which intentionally introduced 'churn' into the results, to display newer or less-popular items so they had a chance to receive clicks and therefore actual ranking data. YouTube is in the business of serving as much content as possible; therefore they need to promote material which is new or similar to what is requested in order to remain a relevant site.
What you're looking for is a 'SpaceX Channel', a feature YouTube also supports. (https://www.youtube.com/user/spacexchannel)

Now, back to the topic of the thread, please.

[ugordan]

I noticed this wire in John Kraus's launch photo. I don't recall seeing it before. Any ideas what this is?

99% that it's a string attached to a tyvek cover on one of the landing leg air vents. They're tied down to the hold downs somewhere and are supposed to pull the covers off at liftoff, but sometimes they break at the wrong end apparently.

[Spudley]

TESS is going to have a very interesting life of its own once it starts producing data.

This thread is in the SpaceX section and is really more about the launch and the rocket than about TESS, so will there be new separate threads for TESS itself and its work elsewhere on the site at some point?

[Ben the Space Brit]

There is a separate TESS thread for spacecraft flight operations and science results.

https://forum.nasaspaceflight.com/index.php?topic=31927.0

[toruonu]

Actual TESS orbit before first apogee burn according to Space-track.

NORAD   SATNAME   INTLDES      PERIOD      INCL   APOGEE   PERIGEE
43435   TESS         2018-038A   10244.32   29.54   299450   296

Did they overperform? I remember apogee target of 270k km.

[Joffan]

That's a 7-day orbital period, and they have a couple of orbits before the moon flyby to adjust the timing perfectly. It's good.

[ulm_atms]

Actual TESS orbit before first apogee burn according to Space-track.

NORAD   SATNAME   INTLDES      PERIOD      INCL   APOGEE   PERIGEE
43435   TESS         2018-038A   10244.32   29.54   299450   296

Did they overperform? I remember apogee target of 270k km.

Yes...but the first few orbits had burns to get the apogee to 400km before the Lunar flyby.  If anything, I would think this should save TESS some fuel.

Link to explain how it gets to its orbit: https://tess.mit.edu/science/

EDIT:  Is it possible the apogee is different due to the initial scrub?  I would think trying to time a lunar flyby would have changes each day in order to intercept it correctly.

[AncientU]

Actual TESS orbit before first apogee burn according to Space-track.

NORAD   SATNAME   INTLDES      PERIOD      INCL   APOGEE   PERIGEE
43435   TESS         2018-038A   10244.32   29.54   299450   296

Did they overperform? I remember apogee target of 270k km.

Yes...but the first few orbits had burns to get the apogee to 400km before the Lunar flyby.  If anything, I would think this should save TESS some fuel.

Link to explain how it gets to its orbit: https://tess.mit.edu/science/

EDIT:  Is it possible the apogee is different due to the initial scrub?  I would think trying to time a lunar flyby would have changes each day in order to intercept it correctly.

Didn't F9 have sufficient capability to deliver TESS directly to its final orbit, or nearly so, and saved the maneuvering? 
(Could have sent it to Mars... listed at 4,020kg to Mars on web page.)