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It's also not a case of dust settling gently on things as it does in an atmosphere, but particles can end up travelling at extreme speeds which effectively sand

It's also not a case of dust settling gently on things as it does in an atmosphere, but particles can end up travelling at extreme speeds which effectively sand-blast anything they come into contact with. Lots of engineering problems to solve here.

dredmorbius 8y ago
The sandblasting effect was observed during the Apollo missions. Apollo 12 landed about 200m from Surveyor 3, an earlier unmanned lunar mission. https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_20090903_apollo12.html https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/... The total amount of dust displaced per landing is estimated at about a ton, moving at 400m/s (900 mph), and travelling easily 3km, with lighter dust being blasted into orbit. Alan Bean's mission gave us an absolutely unique chance to really measure this blowing dust. After landing, Pete and Alan walked over to the S3 spacecraft and cut off pieces that had been subjected to the intense sandblasting of their LM landing just 160 m away. As Alan rounded the large "Surveyor Crater" and approached the S3 spacecraft he said to mission control via radio, "I thought you said this spacecraft is supposed to be white." (Not exact quote - I'm going from memory here.) Mission Control asked "Why? What color is it?" Alan said "It's brown!" This set off a lot of discussion back here on Earth. What did the lunar environment do to that spacecraft to change it from white to brown??? The leading theory was that radiation changed the chemistry of the paint. That theory held for 40 years. Around me 2008 I traveled to Houston and officially checked out all the white painted pieces that had been cut off the S3 spacecraft and returned to Earth by Apollo 12.... We used Scanning Electron Microscopes, laser scanners, X-ray photoionization spectroscopy, and electron dispersive spectroscopy. We discovered the paint's surface was penetrated by sand-sized (100 micron) lunar soil particles travelling about 400 m/s. Each one made a pinhole in the paint, and we could see the soil particle lying in the bottom of each tiny hole. http://www.collectspace.com/ubb/Forum29/HTML/001900.html http://www.collectspace.com/ubb/Forum29/HTML/001900.html

dredmorbius 8y ago

The sandblasting effect was observed during the Apollo missions. Apollo 12 landed about 200m from Surveyor 3, an earlier unmanned lunar mission. https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_20090903_apollo12.html https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/... The total amount of dust displaced per landing is estimated at about a ton, moving at 400m/s (900 mph), and travelling easily 3km, with lighter dust being blasted into orbit. Alan Bean's mission gave us an absolutely unique chance to really measure this blowing dust. After landing, Pete and Alan walked over to the S3 spacecraft and cut off pieces that had been subjected to the intense sandblasting of their LM landing just 160 m away. As Alan rounded the large "Surveyor Crater" and approached the S3 spacecraft he said to mission control via radio, "I thought you said this spacecraft is supposed to be white." (Not exact quote - I'm going from memory here.) Mission Control asked "Why? What color is it?" Alan said "It's brown!" This set off a lot of discussion back here on Earth. What did the lunar environment do to that spacecraft to change it from white to brown??? The leading theory was that radiation changed the chemistry of the paint. That theory held for 40 years. Around me 2008 I traveled to Houston and officially checked out all the white painted pieces that had been cut off the S3 spacecraft and returned to Earth by Apollo 12.... We used Scanning Electron Microscopes, laser scanners, X-ray photoionization spectroscopy, and electron dispersive spectroscopy. We discovered the paint's surface was penetrated by sand-sized (100 micron) lunar soil particles travelling about 400 m/s. Each one made a pinhole in the paint, and we could see the soil particle lying in the bottom of each tiny hole. http://www.collectspace.com/ubb/Forum29/HTML/001900.html http://www.collectspace.com/ubb/Forum29/HTML/001900.html