Astrobotic PM-1 mission, CLPS mission with NASA and commercial payloads |
Astrobotic PM-1 mission, CLPS mission with NASA and commercial payloads |
Feb 4 2022, 03:12 AM
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#16
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Solar System Cartographer Group: Members Posts: 10191 Joined: 5-April 05 From: Canada Member No.: 227 |
I am starting a new thread for this mission which should fly this year.
Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PD: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Jan 9 2024, 08:05 AM
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#17
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Member Group: Members Posts: 124 Joined: 3-September 12 From: Almeria, SE Spain Member No.: 6632 |
Update #6:
"An ongoing propellant leak [...]" "[...] in a stable sun pointing state for approximately 40 more hours, [...]" https://twitter.com/astrobotic/status/1744543629392134194 Anything known about what caused this propellant leak? Thorsten |
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Jan 9 2024, 04:41 PM
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#18
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Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
Anything known about what caused this propellant leak? I haven't heard anything, and there is not much public detail about Peregrine's propulsion system. But it started right after the system was pressurized and was large enough to disturb blankets. I can think of three root causes: 1) damage during launch vibration (hopefully unlikely since the spacecraft was vibe-tested); 2) propellant migration causing a small explosion that blew a hole in the plumbing; 3) pressure regulator failure leading to overpressurization. Assuming https://www.nasa.gov/stmd-game-changing-dev...in-space-talos/ describes what they ended up flying, the main engines were MON-25/MMH biprops but how the attitude-control thrusters (presumably monoprops) were tied in, I have not seen. -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
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Jan 9 2024, 11:01 PM
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#19
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Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
...3) pressure regulator failure leading to overpressurization. Astrobotic is now saying QUOTE Astrobotic’s current hypothesis about the Peregrine spacecraft’s propulsion anomaly is that a valve between the helium pressurant and the oxidizer failed to reseal after actuation during initialization. This led to a rush of high pressure helium that spiked the pressure in the oxidizer tank beyond its operating limit and subsequently ruptured the tank. This seems odd to me, since usually such a valve would open just once and then a downstream regulator would maintain system pressure at the desired safe level. But it sounds like they tried to avoid needing a regulator by just burping the valve open briefly (in hindsight maybe not such a good idea.) -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
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Jan 12 2024, 02:34 PM
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#20
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Member Group: Members Posts: 684 Joined: 24-July 15 Member No.: 7619 |
QUOTE This seems odd to me, since usually such a valve would open just once and then a downstream regulator would maintain system pressure at the desired safe level. But it sounds like they tried to avoid needing a regulator by just burping the valve open briefly (in hindsight maybe not such a good idea.) That valve trouble sounds similar to Apollo 6, which was damaged due to valves opening and causing \'pogo\' shockwaves / water hammer effects in the piping. QUOTE I wonder if they still have enough control to do minor trajectory corrections. I wonder if the rover\'s battery capacity could be tapped to extend the mission\'s data collection, ala Apollo 13? If there rover battery is isolated, then try and deploy the rover, perhaps the existing spin could launch the rover into a slightly different trajectory? You wouldn\'t change the distance much, but perhaps get enough separation to generate \'stereo impacts\' for seismic monitoring? PostScript- looks like the lander is exposed to space and could be let loose? |
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Lo-Fi Version | Time is now: 12th June 2024 - 03:38 PM |
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