Hey Joe (Bauman): Remembering your initial comments about the apparent cohesion of the Martian soil, in the apparent absence of water, when it struck me that the lunar soil had similar properties. Remember how it clung to everything, and left crisp boot impressions, almost as if it were slightly damp? Perhaps looking for old Apollo reports on the subject may shed light on what's going-on with Martian soil. C. __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free web site building tool. Try it! http://webhosting.yahoo.com/ps/sb/
Great point. What's strange is that the soil at Spirit's site and that at Opportunity's seem to have different properties. Spirit's looks much more gummy, with those scrape marks. Spirit's seems to take impressions much more strongly, but not to stick to things -- you can see the seams of the airbags in the "lillypad" impressions made when the lander was bouncing along, yet the airbags are not covered with dirt the way Spirit's are. Very odd. -- Joe
Joe Bauman wrote:
...yet the airbags are not covered with dirt the way Spirit's are. Very odd. -- Joe
A reporter asked about that in one of the MER press conferences. The answer was that the parts of the bags seen in the pictures were the parts closest to the lander and therefore did not contact the ground. Patrick
Here's a neat Russian paper: http://selena.sai.msu.ru/Symposium/phmp-ls.pdf It details the physical and mechanical properties of lunar soil. Much of the data was gathered via robotic probes & the samples they returned, though in-situ data was obviously estimated. I would think that it's being done all over again for Martian soils, albeit more slowly due to a lack of samples, but much can be infered from wheel & airbag impressions, knowing the masses, forces and surfaces that made them. Couple of lunar soil factoids: The soil is remarkably similar all over the lunar surface, and it averages about 4" deep. C. __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free web site building tool. Try it! http://webhosting.yahoo.com/ps/sb/
participants (3)
-
Chuck Hards -
Joe Bauman -
Patrick Wiggins