Mars Sample Return Options

[John Whitehead]

Terrific news that real money will flow to MSR, and here is another quote from the same article.

Phase A... the program will mature critical technologies and make critical design decisions

These two steps will include figuring out how big the MAV really needs to be, and how much payload it really can carry (with or without the fetch rover on the same lander). During the December 16 meeting of the Steering Group for the Planetary Decadal Survey, there was a fine explanation from retired Pegasus launch vehicle developer Antonio Elias, of the MSR Independent Review Board. He said launch vehicle development typically starts with a payload mass goal, then they figure out how big the vehicle needs to be. Conversely, he noted that Pegasus started with a vehicle size (so it could be carried by the airplane), and the engineering challenge was to get the most payload that they could. He said the MAV is the first launch vehicle development to start out with fixed constraints on both ends (required payload mass to Mars orbit, and a total mass limit for delivery to Mars). This is going to be a cool project!

A video of this week's meeting might end up at the following link (not there at the moment, but some other recent meeting videos have been posted).
https://www.nationalacademies.org/event/12-...-2032-meeting-7

[mcaplinger]

These two steps will include figuring out how big the MAV really needs to be, and how much payload it really can carry...

As noted upthread, back in April 2020 NASA showed every indication that they were ready to buy the flight rocket motors from NGIS ( https://beta.sam.gov/opp/349cbd728ab24d7693...true&page=1 )
One presumes that this never happened, reason unknown.

I've seen progress. It doesn't look like this.

[John Whitehead]

One presumes that this never happened, reason unknown.

See Post number 389 above, second paragraph under the heading "summary of events" in 2020, namely that it is hard to nail down how big the MAV is going to be. So the choices are:
1. Buy the motors, build prototype MAVs and do some test flights (expensive testing with evolutionary progress toward a final design like SpaceX does), or
2. Continue trying to converge toward a final design on paper (less costly like ULA is doing for the Vulcan launch vehicle, but harder to do for the MAV in the absence of sufficient experience building miniature launch vehicles).

[Steve G]

Is the sample return mission going to be NASA's next planned Mars mission? I see nothing on the books for any approved, or even a firm proposal, past Perseverance for a NASA Mars mission. When can we expect approval for the next mission?

[mcaplinger]

Is the sample return mission going to be NASA's next planned Mars mission?

Currently yes, though not yet committed to AFAIK (it's been "approved for phase A" but I'm not convinced it's fully funded at that level in the FY2021 budget, maybe somebody who's waded through the budget knows more.)

MEPAG docs are the best source of information. https://mepag.jpl.nasa.gov/meetings.cfm

https://mepag.jpl.nasa.gov/meeting/2021-01/...1_2021%20V5.pdf

https://mepag.jpl.nasa.gov/meeting/2021-01/...2021%20v1.1.pdf

[mcaplinger]

it's been "approved for phase A" but I'm not convinced it's fully funded at that level in the FY2021 budget, maybe somebody who's waded through the budget knows more.

http://spaceref.com/news/viewsr.html?pid=54522 says

Exceeding NASA’s request, Congress is providing $264 million for the Mars Sample Return mission, with direction to have it ready for the launch window that opens in 2026.

[John Whitehead]

After the MSR presentation to MEPAG on 2021Jan27 (middle link in Post number 395 above), one of the questions was whether the MSR schedule and budget includes iterative building and testing to converge on a final MAV design, considering that uncertainty remains after years of past trade studies. The NASA HQ reply was that analysis should be sufficient, and testing will only be needed to validate the design. This statement seems to lean toward option 2 in Post 393.

The Q&A described here starts at time 2:14:30 in the following video of the meeting.
https://mepag.jpl.nasa.gov/meeting/2021-01/...l%20Meeting.mp4

[Explorer1]

Some good details about the fetch rover and MAV in this PBS documentary (around 40 min in): https://www.youtube.com/watch?v=fhtw7Dpntb4
Worth watching on its own, too!

[John Whitehead]

Thanks for that link. Yes there are good details about the fetch rover, especially that prototype testing is ongoing. But there are no details about the MAV, only that it is a "pint size rocket" (not true) and the statement from ESA that the MAV is the hardest part of the whole mission, "super ambitious" (true). Then the animation shows the entire MAV reaching Mars orbit, without dropping the first stage (huh?). One has to wonder why the crack team of miniature launch vehicle engineers was not featured in this NOVA show, testing their prototype rockets and explaining the challenges they are working on.