IPB

Welcome Guest ( Log In | Register )

36 Pages V  « < 34 35 36  
Reply to this topicStart new topic
Mars Sample Return
StargazeInWonder
post Mar 13 2024, 06:24 AM
Post #526


Member
***

Group: Members
Posts: 216
Joined: 14-January 22
Member No.: 9140



Yeah, I'd say that the newer article basically contains one literal bit of new information, which is that the plans are, in their view, on pace.

n is small, but so far China's track record of accomplishing their stated objectives in space exploration seems solid.

From the standpoint of their effort having scientific value, I wonder if they will return any sedimentary rocks and/or if they will complicate their MSR plans by making the effort to do so, or maximize simplicity, at the cost to science, by just grabbing any samples and returning them.

So far, every martian meteorite in possession is igneous. China has suggested that Chryse Planitia might be the site where they would attempt to sample, given the abstract of this paper:

https://agupubs.onlinelibrary.wiley.com/doi...29/2023JE007937

Mars Pathfinder suggests that a landing site in / near Chryse might be able to access some sedimentary samples.
Go to the top of the page
 
+Quote Post
John Whitehead
post Mar 17 2024, 01:41 AM
Post #527


Junior Member
**

Group: Members
Posts: 97
Joined: 17-September 07
Member No.: 3901



QUOTE (from the second link in Post #523 @ Mar 7 2024, 06:23 AM) *
In the budget agreement released Sunday, lawmakers clarified that the ultimatum in the Senate’s proposal was no longer on the table.
Good news, recalling that the Senate in 2023 threatened to cancel MSR if the mission could not be squeezed into the optimistic budget and schedule.

QUOTE (vjkane Post #498 @ Nov 14 2023, 05:52 AM) *
Immediate future work will focus on the system to deliver the samples to orbit. It could mean that NASA would launch the samples into orbit and then collect them some (maybe many years) later. I don't believe that's what is meant.
Hopefully the meaning was focusing on rocket technology progress for launching off Mars. The MSR Chief Engineer (new at NASA HQ as of 2023Oct, see post #493) has a testing background, so it will be interesting to see if the official NASA response to the report from the second MSR Independent Review Board (IRB-2) refers to MAV testing, seemingly overlooked in the IRB-2 report (see attachment to post #493).

Regarding the Planetary Society interview with the MSR IRB-2 Chair (Post #494 to #497), I concur with the disappointment that the interview lacked details.

The last few years have shown that the MAV design became heavy enough to need a huge lander, even without a fetch rover riding along. Keeping things big would be the best outcome for science, to bring back the most samples. Compared to past Mars landers, a heavier one might shed less of its entry velocity aerodynamically. Possibly an inflatable decelerator would help to slow it down, or more of the slowing would use rocket propulsion. Another approach would be to make the MAV smaller by reducing its non-propellant mass (lighter rocket hardware and-or fewer samples). In any case, some kind of new engineering seems necessary for the lander, the MAV, or both.

On 2024Mar5, a Mars science committee (MEPAG) stated to the Planetary Science Advisory Committee (PAC) that Mars scientists are looking forward to NASA's response to IRB-2, one slide from that meeting attached below (MEPAGtoPACslide2024Mar5.pdf). After the long wait since October, we will hopefully see a workable path forward for MSR.
Attached File(s)
Attached File  MEPAGtoPACslide2024Mar5.pdf ( 155.62K ) Number of downloads: 25
 
Go to the top of the page
 
+Quote Post
StargazeInWonder
post Mar 17 2024, 08:23 PM
Post #528


Member
***

Group: Members
Posts: 216
Joined: 14-January 22
Member No.: 9140



This feels like someone has turned on the oven to pre-heat it for baking a cake, then decided to form a committee to find a store that sells essential cake ingredients, and agreed to send out a survey to the diners to find out if they want cake, and has ordered a cookbook. The mis-sequence of preparation and planning is almost comically askew. Of course, there's no re-starting the process now. The good news is that the sampling by Perseverance is an asset that has already been accomplished. There are ways to end up with a successful sample return. But there's no way forward that isn't going to end up attracting negative attention to how inefficient the path has been.
Go to the top of the page
 
+Quote Post
John Whitehead
post Mar 17 2024, 10:33 PM
Post #529


Junior Member
**

Group: Members
Posts: 97
Joined: 17-September 07
Member No.: 3901



Thanks for the analogy. Yes, the people who set the oven to "preheat" were planning a recipe that turned out to take longer to mix, and they made incorrect assumptions about availability of ingredients. Translating back to MSR, one assumption is that engineering is always a procedural activity, even though there is often a need for iterative creative design-build-test to find what will work.

In addition to MAV capability being beyond the state of the art for small rockets, the Capture, Containment, and Return System (CCRS) in Mars orbit was more than a year behind schedule as of late 2023, according to a report from the NASA Inspector General (IG) on 2024Feb28. https://oig.nasa.gov/docs/IG-24-008.pdf

Page 25 of the IG report explains the importance of not being too heavy to fly, in regards to the CCRS. Strangely there is no mention of the MAV being heavier than expected. Searching the PDF turns up "CCRS" in 84 places, while "MAV" appears only 14 times, referred to as "a rocket" with no further details.

I agree that the sampling by Perseverance is an asset that will make it worth the effort to push MSR forward.
Go to the top of the page
 
+Quote Post
mcaplinger
post Mar 17 2024, 11:56 PM
Post #530


Senior Member
****

Group: Members
Posts: 2502
Joined: 13-September 05
Member No.: 497



QUOTE (John Whitehead @ Mar 17 2024, 03:33 PM) *
In addition to MAV capability being beyond the state of the art for small rockets...

This has been a common theme of yours over the past many many pages of this thread, but the OIG report doesn't highlight anything about MAV development being a concern (other than a $45M budget increase from a MAV motor contractor, page 22). The mass margin discussion on page 25 is about the ERO and its launch and has nothing to do with the MAV.

You may well be right about potential eventual problems with MAV development, but the program has run into plenty of trouble without that worry!


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post

36 Pages V  « < 34 35 36
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 19th March 2024 - 08:06 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member.