Author Topic: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD  (Read 32317 times)

Online Chris Bergin

December 16, 2014
NASA Awards Launch Services Contract for Transiting Exoplanet Survey Satellite

NASA has selected SpaceX to provide launch services for the Transiting Exoplanet Survey Satellite (TESS) mission. TESS will launch aboard a Falcon 9 v1.1 launch vehicle, with liftoff targeted for August 2017 from Cape Canaveral Air Force Station in Florida.

The total cost for NASA to launch TESS is approximately $87 million, which includes the launch service, spacecraft processing, payload integration, tracking, data and telemetry, and other launch support requirements.

TESS’s science goal is to detect transiting exoplanets orbiting nearby bright stars. During a three-year funded science mission, TESS will sample hundreds of thousands of stars in order to detect a large sample of exoplanets, with an emphasis on discovering Earth- and super-Earth-sized planets in the solar neighborhood.

The Launch Services Program at NASA's Kennedy Space Center in Florida is responsible for management and oversight of the Falcon 9 v1.1 launch services for TESS. The TESS Mission is led by the Massachusetts Institute of Technology, with oversight by the Explorers Program at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Online abaddon

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #1 on: 12/16/2014 08:21 PM »
Nice to see SpaceX win a NASA contract!  Anyone (Jim) know what tier this satellite is considered?  B?

Here's a little more info on TESS from Gunter's: http://space.skyrocket.de/doc_sdat/explorer_tess.htm.  From that page:

Quote
A launch vehicle has not been selected now, but TESS is baselined with Athena-2c or Taurus-3210, both with additional Star-37FM kick motor. The baselined launch site is Cape Canaveral. Also Antares and Falcon-9 v1.1 are considered.

Sounds like Atlas V was not a consideration.  The satellite is quite light, so I am guessing F9 will be able to do the job without any additional assistance.

Offline ugordan

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #2 on: 12/16/2014 08:25 PM »
The LSP manifest shows TESS as a Medium Class mission.

Atlas V is grossly overpowered for this payload and so is Falcon 9 (I think, that periapsis is rather high...). OSC site states a launch mass of just 325 kg, albeit to a highly eccentric orbit that goes all the way out to the Moon's distance.

So Atlas might not have been even considered. I wonder what that says about the other options like Antares and Athena and their cost?
« Last Edit: 12/16/2014 08:38 PM by ugordan »

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #3 on: 12/16/2014 08:25 PM »
This is the first time I've seen the all inclusive pricing for a full launch services contact for SpaceX published. $62 million for just a rocket, $87 for the whole package....

Offline ugordan

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #4 on: 12/16/2014 08:28 PM »
This is the first time I've seen the all inclusive pricing for a full launch services contact for SpaceX published. $62 million for just a rocket, $87 for the whole package....

Jason-3 contract price was also published over 2 years ago.

Online Comga

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #5 on: 12/16/2014 08:43 PM »
This is the first time I've seen the all inclusive pricing for a full launch services contact for SpaceX published. $62 million for just a rocket, $87 for the whole package....

Let's hope this is one of the hypothesized "$6-10M" RTLS flights.
Of course, if they try there will be people on this forum complaining that SpaceX is not prioritizing the payload by reserving fuel for boost-back.   :o
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Offline ncb1397

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #6 on: 12/16/2014 08:43 PM »
So Atlas might not have been even considered. I wonder what that says about the other options like Antares and Athena and their cost?

Probably more to do with reliability questions than it does cost given Athena was out of production for so long with a bad track record to boot and Antares is undergoing a re-design with a very recent failure.

« Last Edit: 12/16/2014 08:45 PM by ncb1397 »

Offline joshcryer

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #7 on: 12/16/2014 08:45 PM »
Fantastic news for SpaceX and TESS. TESS is going to be a Kepler on steroids. It's going to really nail planets around down sun-like stars. Every time the TESS folks do a presentation you will be shocked by the numbers they're expecting. 20 million stars at 30 minute cadence (Kepler's ability). It also has one of the most fascinating orbital mechanics I've ever seen. Should be stable for decades without station keeping.

Here's a good overview:


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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #8 on: 12/16/2014 08:51 PM »
Probably more to do with reliability questions than it does cost given Athena was out of production for so long with a bad track record to boot and Antares is undergoing a re-design with a very recent failure.

Maybe the orbit requirement (108 000 km periapsis) makes it difficult to do with solid upper stage vehicles. That leaves what, 1 Delta II out of VAFB and F9?

Nevermind that, just saw the orbital insertion plan in the video above. It's your "basic" GTO/TLI-type injection from LEO, but goes out to a 250 000 km apogee and the spacecraft does the rest of the maneuvering work.
« Last Edit: 12/16/2014 09:09 PM by ugordan »

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #9 on: 12/16/2014 09:13 PM »
Nice to see SpaceX win a NASA contract!  Anyone (Jim) know what tier this satellite is considered?  B?

Here's a little more info on TESS from Gunter's: http://space.skyrocket.de/doc_sdat/explorer_tess.htm.  [snip]

Also from that page and the NASA link above the target orbit is  17 Earth Radii × 59 Earth Radii

That requires a two or three burn profile for the second stage.  Something like #1 to a (negative something) by 150 km "orbit", #2 to 150 by 110,000 km (17 Re) #3 to 110,00 by 376,000 km.  With such a light payload it might be possible to go directly from staging to (negative something) by 110,000 and avoid the additional relight.

A quick calculation says that it would take ~64 hours, over 2.5 days, to do the half orbit from LEO to 110,00 km for the last burn.  That's a long time for the second stage to function. 

edit: Per ugordon's edit above "Never Mind".  A fairly nominal suprasyncronous transfer orbit insertion.
« Last Edit: 12/16/2014 09:27 PM by Comga »
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Offline ugordan

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #10 on: 12/16/2014 09:14 PM »
That requires a two or three burn profile for the second stage. 

See my comment above.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #11 on: 12/16/2014 09:55 PM »
Fantastic news for SpaceX and TESS. TESS is going to be a Kepler on steroids. It's going to really nail planets around down sun-like stars. Every time the TESS folks do a presentation you will be shocked by the numbers they're expecting. 20 million stars at 30 minute cadence (Kepler's ability). It also has one of the most fascinating orbital mechanics I've ever seen. Should be stable for decades without station keeping.

Here's a good overview:



At 15:08 there is a good animation of the orbital insertion

Offline Norm38

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #12 on: 12/16/2014 11:50 PM »
That's a great overview video, one of the best I've seen for a science mission.
When they show the mockup with people standing next to it, it's quite small.  Can tell why they need a passively stable orbit, not much room for fuel.

Offline ChrisC

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #13 on: 12/17/2014 12:15 AM »
Fantastic news for SpaceX and TESS. TESS is going to be a Kepler on steroids. It's going to really nail planets around down sun-like stars. Every time the TESS folks do a presentation you will be shocked by the numbers they're expecting. 20 million stars at 30 minute cadence (Kepler's ability). It also has one of the most fascinating orbital mechanics I've ever seen. Should be stable for decades without station keeping.

Here's a good overview:

Fantastic information, thanks joshcryer!

I'm a huge fan of Kepler -- have watched every one of their news conferences, starting before launch.  In fact, just this morning I was listening to this interview with a planetary scientist, talking about Kepler, TESS and JWST.

http://www.planetary.org/multimedia/planetary-radio/show/2014/sara-seager-and-the-search-for-earths-twin.html
« Last Edit: 12/17/2014 05:15 AM by ChrisC »
NASA TV in HD:  history, FAQ and latest status

Offline yg1968

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #14 on: 12/17/2014 03:58 AM »
This NASA press release from a month ago on the next phase for TESS also belongs in this thread:
http://www.nasa.gov/content/goddard/nasa-s-tess-mission-cleared-for-next-development-phase/#.VJEM4iuG-1Q

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #15 on: 12/17/2014 06:53 AM »
I'm a huge fan of Kepler -- have watched every one of their news conferences, starting before launch.  In fact, just this morning I was listening to this interview with a planetary scientist, talking about Kepler, TESS and JWST.

Same here, Borucki made me fall in love with the transit concept when I first learned of Kepler. I later watched an old Neil deGrasse Tyson course (The Inexplicable Universe: Unsolved Mysteries) where he talked about a "promising transit technique that hasn't been tried yet." Turns out it was not just promising, it was the best technique possible. And to think when Borucki first envisioned it the technology didn't even exist yet.

To add to the thread for others interested, TESS has social media pages.

Twitter @ MIT: https://twitter.com/TESSatMIT

Twitter @ NASA: https://twitter.com/NASA_TESS

Web @ MIT: http://space.mit.edu/TESS/

Web @ NASA: http://tess.gsfc.nasa.gov/

Facebook (they update mostly here, but I'm sure it'll change as time gets closer): https://www.facebook.com/NASATESS

Finally, TESS announced that they won't have a proprietary data period, and that they'll be dumping the data to the community as soon as possible on this FB post: https://www.facebook.com/NASATESS/posts/744397388947684

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #16 on: 12/21/2014 03:42 PM »
So Atlas might not have been even considered. I wonder what that says about the other options like Antares and Athena and their cost?
Athena 2c is supposedly priced at $65 million, less than the $87 million now allocated for this Falcon 9 launch, but NASA would also have had to fund a Star 37 kick motor for an Athena 2c launch, not to mention restarting the long-dormant SLC 47 launch site.  Falcon 9 probably also provides a lot more wiggle room on weight growth.

I wonder where the second stage will be disposed.

 - Ed kyle
« Last Edit: 12/21/2014 04:08 PM by edkyle99 »

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #17 on: 12/21/2014 04:58 PM »
Ed, you're comparing a full contract including services to one without.  That is not an apples to apples comparison.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #18 on: 12/21/2014 10:01 PM »
So Atlas might not have been even considered. I wonder what that says about the other options like Antares and Athena and their cost?
Athena 2c is supposedly priced at $65 million, less than the $87 million now allocated for this Falcon 9 launch, but NASA would also have had to fund a Star 37 kick motor for an Athena 2c launch, not to mention restarting the long-dormant SLC 47 launch site.  Falcon 9 probably also provides a lot more wiggle room on weight growth.

I wonder where the second stage will be disposed.

 - Ed kyle
IIRC, the certification cost for the first NASA mission was expected to be 10M. The Athena 2c certification should cost about the same, shouldn't it?

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #19 on: 03/20/2015 09:32 PM »
NASA | The Search for New Worlds is Here

Published on Mar 20, 2015
The Transiting Exoplanet Survey Satellite (TESS) is an astrophysics Explorer-class mission between NASA and MIT. After launching in 2017, TESS will use four cameras to scan the entire sky, searching for planets outside our Solar System, known as exoplanets. The mission will monitor over 500,000 of the brightest stars in the sky, searching for dips in their brightness that would indicate a planet transiting across. TESS is predicted to find over 3,000 exoplanet candidates, ranging from gas giants to small rocky planets. About 500 of these planets are expected to be similar to Earth's size. The stars TESS monitors will be 30-100 times brighter than those observed by Kepler, making follow-up observations much easier. Using TESS data, missions like the James Webb Space Telescope can determine specific characteristics of these planets, including whether they could support life.

Tony De La Rosa

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #20 on: 03/21/2015 01:31 AM »
So Atlas might not have been even considered. I wonder what that says about the other options like Antares and Athena and their cost?
Athena 2c is supposedly priced at $65 million, less than the $87 million now allocated for this Falcon 9 launch, but NASA would also have had to fund a Star 37 kick motor for an Athena 2c launch, not to mention restarting the long-dormant SLC 47 launch site.  Falcon 9 probably also provides a lot more wiggle room on weight growth.

I wonder where the second stage will be disposed.

 - Ed kyle

Didn't ULA have one more Delta II to bid with?   
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #21 on: 03/21/2015 01:40 AM »
In some of Tory Bruno's interviews he has mulled it not being worth the effort to sell the last white tail.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #22 on: 03/21/2015 01:47 AM »
I don't think Delta II would be competitive with Falcon 9 now.  The article I found on last Delta II purchases said NASA paid $400M for 3 flights (including processing and everything else).  SpaceX has been offering that for less than $90M/flight.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #23 on: 03/21/2015 12:48 PM »
I don't think Delta II would be competitive with Falcon 9 now.  The article I found on last Delta II purchases said NASA paid $400M for 3 flights (including processing and everything else).  SpaceX has been offering that for less than $90M/flight.

That makes the last Delta II cost more than a Atlas V: D II $133M to Atlas V 401 $120M. So yes it is not worth the effort.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #24 on: 03/21/2015 12:53 PM »
NASA pays more than $120m for an Atlas V.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #25 on: 03/21/2015 01:48 PM »
NASA pays more than $120m for an Atlas V.
Yes, I believe that they pay something like 180 for a 401 and 320 for a 551.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #26 on: 03/21/2015 03:55 PM »
Quote

Didn't ULA have one more Delta II to bid with?

Can only be launch from SLC-2W at VAFB. Which ULA might want to close down after the 2017 ICESat-2 mission to further reduce the upkeep cost for their pads.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #27 on: 03/21/2015 04:05 PM »
SLC-2 is owned by NASA

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #28 on: 03/21/2015 04:18 PM »
SLC-2 is owned by NASA
Was thinking of the staffing & GSE cost for the pad.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #29 on: 03/21/2015 06:26 PM »
I don't think Delta II would be competitive with Falcon 9 now.  The article I found on last Delta II purchases said NASA paid $400M for 3 flights (including processing and everything else).  SpaceX has been offering that for less than $90M/flight.

That makes the last Delta II cost more than a Atlas V: D II $133M to Atlas V 401 $120M. So yes it is not worth the effort.

The latest (and probably final) Delta II launch for IceSat-2 was about $97M. But they might not have been able to offer that price for TESS.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #30 on: 05/27/2016 01:53 PM »
Tweet from Sara Seager
Quote
Looks like we’ll be spending Xmas 2017 at Cape Canaveral. New TESS launch date “no earlier than 20 December, 2017”

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #31 on: 10/07/2016 08:23 AM »
NASA’s TESS Mission Will Provide Exciting Exoplanet Targets for Years to Come

NASA's search for planets outside of our solar system has mostly involved very distant, faint stars. NASA’s upcoming Transiting Exoplanet Survey Satellite (TESS), by contrast, will look at the brightest stars in our solar neighborhood.

After TESS launches, it will quickly start discovering new exoplanets that ground-based observatories, the Hubble Space Telescope and, later, the James Webb Space Telescope, will target for follow-up studies. TESS is scheduled to launch no later than June 2018. Astronomers are eagerly anticipating the possibility that, in the near future, all three space missions could be studying the sky at the same time.

“The problem is that we’ve had very few exoplanet targets that are good for follow-up,” said TESS Project Scientist Stephen Rinehart at NASA's Goddard Space Flight Center in Greenbelt, Maryland. “TESS will change that.”

Planets around closer, brighter stars are ideal for follow-up study because they'll produce stronger signals than planets around more distant stars. These planets have a higher signal-to-noise ratio, which measures the ratio of useful information — the signal — to non-useful information — the noise — that a telescope receives. These signals might also include a chemical sampling of an exoplanet's atmosphere, which is an exciting prospect for scientists hoping to search for signs of life on distant worlds.

TESS will do the initial roundup of exoplanets, with the potential to identify thousands during its projected two-year mission. One of TESS’ main science goals is to identify 50 rocky worlds, like Earth or Venus, whose masses can be measured.

“The search for exoplanets is a bit like a funnel where you pour in lots of stars,” said TESS Deputy Science Director Sara Seager at the Massachusetts Institute of Technology (MIT), Cambridge. “At the end of the day, you have loads of planets, and from there you need to find the rocky ones.”

The TESS Science Center will help identify and prioritize the TESS Objects of Interest (TOI) for follow-up. TOI are objects that scientists believe could be exoplanets based on TESS data. Ground-based telescopes will confirm which TOI are exoplanets, and from there will help determine which are rocky. The center is a partnership between MIT's Physics Department and Kavli Institute for Astrophysics and Space Research — where TESS Principle Investigator George Ricker resides — the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, and NASA’s Ames Research Center in Moffett Field, California.

The main thing space- and ground-based telescopes hope to find out about the TESS targets with follow-up observations is what these exoplanet atmospheres are like. Exoplanet atmosphere exploration is one of the Webb telescope's four main science goals.

NASA's Webb telescope and ground-based telescopes will determine the atmospheres of exoplanets using spectroscopy. In this process, telescopes look at the chemical signatures of the light passing through exoplanet atmospheres. This signature can tells scientists what chemicals are in the planetary atmosphere, and how much of each there are. It can also help scientists determine whether a planet could be habitable.

“There are a couple of things we like to see as a potential for habitability – one of them is water, which is probably the single most important, because as far as we know, all life that we’re familiar with depends on water in some way,” Rinehart said. “The other is methane, which on our Earth is produced almost entirely biologically. When you start seeing certain combinations of all of these things appearing together – water, methane, ozone, oxygen – it gives you a hint that the chemistry is out of equilibrium. Naturally, planets tend to be chemically stable. The presence of life throws off this balance.”

Exoplanets aren’t the only science that will come out of the TESS all-sky survey, however. While scientists expect to spot a transit signal that could reveal exoplanets around only about one out of 100 stars, virtually every star in the sky will be monitored carefully and continuously for at least 27 days, resulting in a wide variety of variability to be explored.

The TESS Guest Investigator (GI) Program will allow for deeper investigations of astronomically interesting objects, either through TESS data alone, or by identifying interesting variables for further study with the Webb telescope, Hubble and other ground- and space-based telescopes. The GI Program will look at variable objects, such as flare stars, active galaxies and supernovae, and may even discover optical counterparts to distant transient events, such as gamma-ray bursts. Only the number and type of exciting proposed ideas the program receives limit what TESS will find through the GI Program.

Between the mission’s exoplanet survey and the GI Program, TESS will provide the best follow-up targets for many missions to come.

“TESS not only will provide targets for the Webb telescope, but for every telescope we plan to build on the ground and in space over the next two decades,” said Mark Clampin, director of the Astrophysics Science Division at Goddard. With such an exciting future, scientists from around the world are watching the progress of the TESS mission, and anxiously awaiting its launch.

Related Links

NASA's TESS website
TESS project website
By Elaine Hunt
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Last Updated: Oct. 5, 2016
Editor: Rob Garner

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #32 on: 10/07/2016 09:48 AM »
The thread title still says v1.1, but I assume TESS will be launched on a F9 v1.2 instead?

Offline AbuSimbel

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #33 on: 10/07/2016 12:35 PM »
The thread title still says v1.1, but I assume TESS will be launched on a F9 v1.2 instead?
Or 1.3 as suggested by recent news  ;) maybe it's better to remove the v number altogether

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #34 on: 10/07/2016 07:28 PM »
Let's not go down the "is Falcon the US Proton" road, ok?

I actually had a warning queued up earlier but figured you all weren't going to go down that road...
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Offline Mader Levap

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #35 on: 10/07/2016 08:07 PM »
It is a good thing then that this is not launched on something that "de facto" is the American version of Proton.
Well, since Lar warned against discussing F9 vs Proton, I will say just that: two failures in 14 months is unacceptable. Period. No wild handwaves nor endless excuses will change that.

I do not want for F9 to launch anything important (read: costing billions) any time soon. It must prove itself all over again from scratch.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #36 on: 10/07/2016 08:10 PM »
It is a good thing then that this is not launched on something that "de facto" is the American version of Proton.
Well, since Lar warned against discussing F9 vs Proton, I will say just that: two failures in 14 months is unacceptable. Period. No wild handwaves nor endless excuses will change that.

I do not want for F9 to launch anything important (read: costing billions) any time soon. It must prove itself all over again from scratch.
Take it to another thread. Second warning.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #37 on: 10/09/2016 10:34 AM »
I didn't realized that a) TESS was going to fly next year and b) it was booked to a Falcon 9. Considering Kepler (including the K2 mission) outstanding results, I just can't imagine what TESS results will be.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #38 on: 10/11/2016 06:36 AM »
I didn't realized that a) TESS was going to fly next year and b) it was booked to a Falcon 9. Considering Kepler (including the K2 mission) outstanding results, I just can't imagine what TESS results will be.

The article above says "TESS is scheduled to launch no later than June 2018." Considering how spacecraft and launches are so often delayed, I would expect a launch to be in 2018.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #39 on: 10/11/2016 04:49 PM »
The thread title still says v1.1, but I assume TESS will be launched on a F9 v1.2 instead?
Or 1.3 as suggested by recent news  ;) maybe it's better to remove the v number altogether
Tweet from Sara Seager
Quote
Looks like we’ll be spending Xmas 2017 at Cape Canaveral. New TESS launch date “no earlier than 20 December, 2017”
I didn't realized that a) TESS was going to fly next year and b) it was booked to a Falcon 9. Considering Kepler (including the K2 mission) outstanding results, I just can't imagine what TESS results will be.

The article above says "TESS is scheduled to launch no later than June 2018." Considering how spacecraft and launches are so often delayed, I would expect a launch to be in 2018.

According to their website, all of the above are true.  It still says launch is on F9 v1.1 (despite that launcher no longer existing) and gives both December 2017 as the working launch date and June 2018 as the NLT date.

Quote
SpaceX Falcon 9 v1.1 Launch Vehicle
Quote
The TESS launch date is NLT June 2018 (the current working launch date is December 2017).

https://tess.gsfc.nasa.gov/launch.html

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #40 on: 12/25/2016 06:38 PM »


This is a SETI video on TESS.



It includes immediately after this at 26 minutes or so a short discussion of the launcher, along with some shots of TESS structural fit testing on a F9 mockup. And a ridiculous to-scale in the fairing image.
At about 1:01, there is a discussion of the original designs, and the plans for launching on the orbital sciences Taurus/Minotaur-C which has a maximum payload to LEO of 1350kg but by the time the vehicle got picked, it was too late to optimise.
F9 was the lowest bidder..

Other notable facts - it ends up in its final 14 day orbit which is metastable, and the anticipation is that they need 50 or so grams of fuel a year to do desaturations. It has 20kg of fuel remaining of the 40kg initial hydrazine, and no other consumables.

"Launch around the end of 2017, maybe a bit later" - which is consistent with above in thread.
(odd - for some reason the thread title was accidentally changed)
« Last Edit: 12/26/2016 05:15 AM by speedevil »

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #41 on: 01/02/2017 08:22 PM »
Quote
Jeff Foust – ‏@jeff_foust
At #ExoPAG mtg, NASA’s Martin Still says TESS exoplanet mission on track, but Dec. launch on F9 could slip due to SpaceX schedule issues.

https://mobile.twitter.com/jeff_foust/status/816015605748867073

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #42 on: 01/05/2017 08:44 PM »
Quote
Jeff Foust –  ‏@jeff_foust

Hertz’s chart of missions shows a Dec 2017 launch date for TESS. But hearing launch schedule issues will delay it to early 2018. #AAS229

https://mobile.twitter.com/jeff_foust/status/817090471377780736

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #43 on: 01/05/2017 10:08 PM »
This shouldn't be surprising since TESS is like number 30 something on SpaceX's launch manifest...

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #44 on: 01/06/2017 06:07 PM »
Tweet from NASA_TESS
Quote
After review of the SpaceX Falcon 9 launch vehicle certification schedule & anomaly recovery @NASA_TESS launch date has moved to NET 3/20/18

No surprise there, middle of the previously stated December to June window.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #45 on: 03/28/2017 06:00 PM »
Tweet from Jeff Foust:
Quote
Hertz adds TESS launch on a Falcon 9 slipped from December 2017 to March 2018 because of NASA launch vehicle certification delays.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #46 on: 03/28/2017 09:26 PM »
Tweet from Jeff Foust:
Quote
Hertz adds TESS launch on a Falcon 9 slipped from December 2017 to March 2018 because of NASA launch vehicle certification delays.

There are now about five posts in a row giving the same delay but with evolving reasons:
"... F9 could slip due to SpaceX schedule issues."
"After review of the SpaceX Falcon 9 launch vehicle certification schedule & anomaly recovery @NASA_TESS launch date has moved .."
"...because of NASA launch vehicle certification delays."
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #47 on: 03/29/2017 02:13 PM »
And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

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And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

TESS is 350 kg - so yes. Very RTLS.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #49 on: 03/29/2017 04:11 PM »
And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

TESS is 350 kg - so yes. Very RTLS.

Good candate for a falcon 1 type veh or ride share

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #50 on: 03/29/2017 04:38 PM »
And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

TESS is 350 kg - so yes. Very RTLS.

Good candate for a falcon 1 type veh or ride share

The final orbit is a bit unique, which may not be very useful to other spacecraft.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #51 on: 03/29/2017 06:20 PM »
And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

TESS is 350 kg - so yes. Very RTLS.

Good candate for a falcon 1 type veh or ride share

Better is the enemy of good enough.
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #52 on: 03/29/2017 08:17 PM »
And a ridiculous to-scale in the fairing image.

Based on the small size of this payload, I assume this is RTLS? Has that been announced?

TESS is 350 kg - so yes. Very RTLS.

Good candate for a falcon 1 type veh or ride share

Just for the record - the alternatives considered were Athena-2c or Taurus-3210, both with additional Star-37FM, an Antares with kick-motor or the unmodified, but somewhat oversized Falcon-9.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #53 on: 03/29/2017 09:07 PM »
Just for the record - the alternatives considered were Athena-2c or Taurus-3210, both with additional Star-37FM, an Antares with kick-motor or the unmodified, but somewhat oversized Falcon-9.
Interesting, I did not know Antares was certified to carry a Class B (I think?) payload.  Or was anticipated to be certified to do that.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #54 on: 03/29/2017 10:05 PM »
Just for the record - the alternatives considered were Athena-2c or Taurus-3210, both with additional Star-37FM, an Antares with kick-motor or the unmodified, but somewhat oversized Falcon-9.
Interesting, I did not know Antares was certified to carry a Class B (I think?) payload.  Or was anticipated to be certified to do that.
AFAIK, Antares was anticipated to be certified to do that.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #55 on: 03/31/2017 05:48 PM »
Quote
A look inside the @NASA_TESS spacecraft @OrbitalATK; @NASA's next #exoplanet hunter!

https://twitter.com/nasa_tess/status/847866169709166592

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #56 on: 04/01/2017 10:17 AM »
....
Just for the record - the alternatives considered were Athena-2c or Taurus-3210, both with additional Star-37FM, an Antares with kick-motor or the unmodified, but somewhat oversized Falcon-9.

Out of the launch alternatives, the Falcon 9 was the low bid for the TESS mission. No wonder LockMart shelf the Athena. Since it appears to be non-competitive. Think it will get worst for the small sat launch providers, now that the "flight proven"  Falcon 9 enters the picture.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #57 on: 05/19/2017 05:54 PM »
From the recent GAO overview of NASA projects (pdf file) that has been mentioned in a couple other threads:

Quote
Cost and Schedule Status
The TESS project delayed its launch readiness date by 7 months from August 2017 to March 2018 due to launch vehicle and instrument-related delays, but it still plans to launch before its committed launch date and within its cost baseline. ...

Launch
According to NASA officials, several launch vehicle related issues led to the delay in TESS’s planned launch date. First, SpaceX required additional time to certify its upgraded Falcon 9 through NASA’s Launch Services Program since it will be the first time that NASA will use this version of the vehicle. The certification process includes criteria, such as having six successful launches. In addition, SpaceX needed time to investigate and resolve an anomaly that caused a September 2016 launch mishap. NASA has renegotiated its launch contract with SpaceX to account for these delays. SpaceX continues to upgrade the Falcon 9 and, as part of the negotiation process, NASA gained the right not to be the first launch on the planned Block 5 version of the vehicle.

PROJECT OFFICE COMMENTS
In commenting on a draft of this assessment, TESS project officials said they are on track to meet their March 2018 launch date, and are holding a significant amount of schedule reserves

Hopefully Block 5 will be flying before TESS anyway.  I assume it can fly on Block 5 if that version of the rocket has some successful launches by then.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #58 on: 06/27/2017 03:15 PM »
Quote
The spacecraft team @OrbitalATK checks out the installation of one of the two solar arrays that will provide power to @NASA's @NASA_TESS.

https://twitter.com/nasa_tess/status/879707138720882689

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #59 on: 07/27/2017 01:58 PM »
http://spacenews.com/cameras-on-nasa-exoplanet-spacecraft-slightly-out-of-focus/

Quote
The TESS team thinks there will be a 10 percent cut in terms of the number of planets that they expect to be able to detect.
Quote
Despite the reduction, Boss said TESS scientists believe they will still be able to meet the mission’s primary science requirements, and thus there is no need to fix the cameras.

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SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #60 on: 07/28/2017 06:43 PM »
http://spacenews.com/cameras-on-nasa-exoplanet-spacecraft-slightly-out-of-focus/

Quote
The TESS team thinks there will be a 10 percent cut in terms of the number of planets that they expect to be able to detect.
Quote
Despite the reduction, Boss said TESS scientists believe they will still be able to meet the mission’s primary science requirements, and thus there is no need to fix the cameras.

Quote
Jeff Foust @jeff_foust
Updated our article on TESS spacecraft camera focus issue with additional NASA comment playing down the problem:

https://mobile.twitter.com/jeff_foust/status/890951536141975553

From the revised article.

Quote
Chou added July 28 that the out-of-focus area is limited to the outer edges of the image, and that “recent testing shows that the camera focus towards the image center is better than originally designed.”
« Last Edit: 07/28/2017 06:45 PM by Star One »

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #61 on: 07/28/2017 07:25 PM »
Well, that makes sense. I am working on scientific instruments, not on TESS though. It is common that the focal surface of some optical system is curved (spherical) but the detector usually flat. There are curved detectors but they are experimental and not used (yet). So imagine a spherical focal surface intersected by a flat detector surface. If you minimize the offset between both surfaces everywhere, both the center and the edges of the flat detector surface are somewhat out of focus. The optimal focus is on a ring somewhere in between. If the optics is such that the edges are more out of focus, by geometry, the center is more in focus, meaning the flat detector surface is closer to the spherical optical focal surface.
For this reason, usually the detector or optics can be pistoned just a little bit to adjust the focus for operational conditions. This is done manually in commissioning and not touched later. Unless the conditions change of course. I am surprised that TESS does not have such a system.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #62 on: 07/29/2017 12:16 PM »
There's a ppt about camera construction and testing here at NTRS:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20160010628.pdf

The cameras are f/1.4, so I expect focusing is going to be dodgy to begin with, with significant field curvature.  As Semmel noted above, the focal "plane" is curved, but the CCDs are not.  The best you can get is some optimal focus, which in the perfect world would cause only minimal PSF (point-spread function, basically the shape of a point source, like a star) variation across the field.  All this can be modeled (see the NTRS paper above, there are PSF models on p. 28) and surely, they thought the optical system design was adequate.  From the SpaceNews article, it sounds like the CCDs might be too far forward or backward on the optical axis (the remark about glue crystallization makes me think of expansion or contraction).

The reason for reduced effectiveness in finding planets is that if you spread the PSF over more pixels, you add noise to the photometry, because each pixel contributes noise.  More noise means you are less sensitive to smaller variations in brightness.  So, near the center of the FOV, all could be well, but the signal-to-noise ratios would be lower than expected farther from the center of the field.

The article says the mission should meet its primary goals, so it's not immediately clear if the PSF is actually out-of-spec, or just not as good as hoped for.  It isn't obvious that anybody even messed up; it could be that the sample tests and such didn't scale up as expected based on some reference formula.  In any case, the final word won't come until TESS is in space and has outgassed and cooled.
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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #63 on: 07/29/2017 08:24 PM »
I didn't check the optical system. F/1.4 is pretty fast indeed. For those who don't know that is the ratio of rays convergence to focus. So imagine a defocus if 5 microns, than the PSF would become larger by 5/1.4=3.5 microns. With such a fast beam, the surface roughness of the CCD becomes problematic. I can't talk about what the surface of our CCDs looks l like, but the lowest to highest point can be more than 10 microns hight difference. This alone can mean that the size of the PSF varies by more than a pixel in diameter over the field, even with perfect optics.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #64 on: 07/30/2017 05:17 AM »
Well, that makes sense. I am working on scientific instruments, not on TESS though. It is common that the focal surface of some optical system is curved (spherical) but the detector usually flat. There are curved detectors but they are experimental and not used (yet). So imagine a spherical focal surface intersected by a flat detector surface. If you minimize the offset between both surfaces everywhere, both the center and the edges of the flat detector surface are somewhat out of focus. The optimal focus is on a ring somewhere in between. If the optics is such that the edges are more out of focus, by geometry, the center is more in focus, meaning the flat detector surface is closer to the spherical optical focal surface.
For this reason, usually the detector or optics can be pistoned just a little bit to adjust the focus for operational conditions. This is done manually in commissioning and not touched later. Unless the conditions change of course. I am surprised that TESS does not have such a system.
There is no curvature of field in the design
(The first two authors are Primeau and Chrisp.  They are terrific optical designers and optimized several orders beyond field curvature.)
That the center is better than expected and the edges worse is probably a complex issue of tolerancing.
And "crystallization" may be a simplification of having the bond material pass its glass transition temperature warmer or colder than expected. Beyond that point the coefficient of thermal expansion changes significantly.
Passive focus of very cold instruments is really tricky. Even for JPL.
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #65 on: 07/30/2017 04:27 PM »
Well, that makes sense. I am working on scientific instruments, not on TESS though. It is common that the focal surface of some optical system is curved (spherical) but the detector usually flat. There are curved detectors but they are experimental and not used (yet). So imagine a spherical focal surface intersected by a flat detector surface. If you minimize the offset between both surfaces everywhere, both the center and the edges of the flat detector surface are somewhat out of focus. The optimal focus is on a ring somewhere in between. If the optics is such that the edges are more out of focus, by geometry, the center is more in focus, meaning the flat detector surface is closer to the spherical optical focal surface.
For this reason, usually the detector or optics can be pistoned just a little bit to adjust the focus for operational conditions. This is done manually in commissioning and not touched later. Unless the conditions change of course. I am surprised that TESS does not have such a system.
There is no curvature of field in the design
(The first two authors are Primeau and Chrisp.  They are terrific optical designers and optimized several orders beyond field curvature.)
That the center is better than expected and the edges worse is probably a complex issue of tolerancing.
And "crystallization" may be a simplification of having the bond material pass its glass transition temperature warmer or colder than expected. Beyond that point the coefficient of thermal expansion changes significantly.
Passive focus of very cold instruments is really tricky. Even for JPL.
Or the corrector plates aren't up to snuff.  F1.4 is extremely fast and making the corrector plates for that kind of optical design really difficult.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #66 on: 07/30/2017 06:27 PM »
Or the corrector plates aren't up to snuff.
This is an all-refractive lens with seven elements, two aspherical.

If you read the report you'll see that the assembly flow is very complex and finicky.  If I had been reviewing this design I'd have been very skeptical that a high level of athermalization was a realistic expectation -- the results don't look too bad to me.

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #67 on: 07/30/2017 06:43 PM »
Or the corrector plates aren't up to snuff.
This is an all-refractive lens with seven elements, two aspherical.

If you read the report you'll see that the assembly flow is very complex and finicky.  If I had been reviewing this design I'd have been very skeptical that a high level of athermalization was a realistic expectation -- the results don't look too bad to me.

Even more routine f/2.0 systems are really hard to get right. 

The ATLAS design, a Wright Schmidt f/2.0 system, which are being used with flat 10Kx10K CCD chips, found their original corrector plates were not well enough made, and have been replacing them.  http://www.fallingstar.com/specifications.php This caused focus problems (rather, you could never get the size images you needed).

I am a member of the Amateur Telescope Makers of Boston.  One of our members is an optical technician who fabricates a lot of precision optics for satellites and ground systems, and I chatted with him about ATLAS's problems. Making big pieces of aspheric glass (with the surfaces different), is really quite hard according to him.  F/1.4 is much more of a nightmare.  If they have "good enough" optics, great. 

ATLAS didn't have "good enough", so had to have them remade, as it makes a factor of five in ATLAS' asteroid detection rate.


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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #68 on: 07/30/2017 07:25 PM »
There's more detail in TESS status update from the recent APAC meeting: https://smd-prod.s3.amazonaws.com/science-red/s3fs-public/atoms/files/Ricker_TESS_APAC_July%202017_v5.pdf

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #69 on: 07/30/2017 09:44 PM »

There is no curvature of field in the design

I think a better statement would be "as far as practical, the focal plane has no curvature".  If you look at the graphs of lens performance (see TESS status, page 10) you will see that if you get best focus in the middle, best focus at 6o degrees off axis needs a 20 micron shift, then 40 microns at 12 o, then back to 20 microns at 16o.  This is pretty typical - best focus typically looks like a low order polynomial in distance from the center.   

The fundamental problem is that a flat focal surface is a very "unnatural" configuration.  Each surface, when varied, produces a smooth radial function of best focus.  But the function is different for every surface, so all you can do is get them to cancel approximately.  This also induces tough constraints on other surfaces as well.

To see how hard optical systems need to work to approximate a flat field is, consider this paper.  By allowing a curved focal plane, with otherwise the same specs, the reduce a design with 14 lenses, 2 aspheres, and 10 types of glass, to a design with 9 lenses, no aspheres, and 3 types of glass.

Or intuitively, how does your eye get such good results for a single lens made of jelly?  A lot of it is because your retina is a strongly curved focal surface.


Offline jg

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #70 on: 07/30/2017 09:51 PM »

There is no curvature of field in the design

I think a better statement would be "as far as practical, the focal plane has no curvature".  If you look at the graphs of lens performance (see TESS status, page 10) you will see that if you get best focus in the middle, best focus at 6o degrees off axis needs a 20 micron shift, then 40 microns at 12 o, then back to 20 microns at 16o.  This is pretty typical - best focus typically looks like a low order polynomial in distance from the center.   

The fundamental problem is that a flat focal surface is a very "unnatural" configuration.  Each surface, when varied, produces a smooth radial function of best focus.  But the function is different for every surface, so all you can do is get them to cancel approximately.  This also induces tough constraints on other surfaces as well.

To see how hard optical systems need to work to approximate a flat field is, consider this paper.  By allowing a curved focal plane, with otherwise the same specs, the reduce a design with 14 lenses, 2 aspheres, and 10 types of glass, to a design with 9 lenses, no aspheres, and 3 types of glass.

Or intuitively, how does your eye get such good results for a single lens made of jelly?  A lot of it is because your retina is a strongly curved focal surface.

Another example of flat image plane, but at very high cost, is the Baker/Schmidt design of LSST.

https://www.lsst.org/about/tel-site/optical_design

It is *really* hard to get a wide flat focal plane of large chunks of sky.

Online Comga

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #71 on: 07/31/2017 03:23 AM »

There is no curvature of field in the design

I think a better statement would be "as far as practical, the focal plane has no curvature".  If you look at the graphs of lens performance (see TESS status, page 10) you will see that if you get best focus in the middle, best focus at 6o degrees off axis needs a 20 micron shift, then 40 microns at 12 o, then back to 20 microns at 16o.  This is pretty typical - best focus typically looks like a low order polynomial in distance from the center.   

The fundamental problem is that a flat focal surface is a very "unnatural" configuration.  Each surface, when varied, produces a smooth radial function of best focus.  But the function is different for every surface, so all you can do is get them to cancel approximately.  This also induces tough constraints on other surfaces as well.

To see how hard optical systems need to work to approximate a flat field is, consider this paper.  By allowing a curved focal plane, with otherwise the same specs, the reduce a design with 14 lenses, 2 aspheres, and 10 types of glass, to a design with 9 lenses, no aspheres, and 3 types of glass.

Or intuitively, how does your eye get such good results for a single lens made of jelly?  A lot of it is because your retina is a strongly curved focal surface.

OK
There isn't just simple Petzval curvature of field.
As you said, it looks like a complex curve that swings backward.
And the second report did indeed say "crystallization" of the bond material.
But I repeat: Passive focus at very cold temperatures is hard, even for MIT.
Curved focal planes are even harder.
edit: Or you can approximate it like the Kepler photometer.
But we are wandering from TESS
« Last Edit: 07/31/2017 03:25 AM by Comga »
What kind of wastrels would dump a perfectly good booster in the ocean after just one use?

Online catdlr

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Re: SpaceX Falcon 9 : TESS : March 2018 : GENERAL THREAD
« Reply #72 on: 08/05/2017 03:22 AM »
TESS Camera Mounting Timelapse

NASA.gov Video
Published on Aug 4, 2017


The four TESS cameras being mounted to the camera plate in preparation for integration to spacecraft at Orbital ATK in Dulles, Virginia.

https://www.youtube.com/watch?v=SOj1PCtG2yk?t=001

Tony De La Rosa

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