[meteorite-list] Photos of fresh impact craters on Mars
Robin Whittle
rw at firstpr.com.au
Fri May 17 11:23:32 EDT 2013
Here are some press releases with photos:
http://www.uanews.org/story/ua-mars-camera-reveals-hundreds-of-impacts-each-year
http://www.jpl.nasa.gov/news/news.php?release=2013-162
The paper itself is behind a paywall:
http://www.sciencedirect.com/science/article/pii/S0019103513001693
Over these photos there is quite a range of colors in the undisturbed
surface, the colour of the craters and the colour of surface where the
ejected material has landed.
I get the impression that Mars would be not such a great place to find
meteorites. It seems that few of them would be slowed enough by the
atmosphere to land at a moderate speed. Gravity is about 0.37 that of
Earth's and the surface pressure is 0.006. Although the scale height is
1.8 times that of Earth's, I guess that the only meteorites which fall
to the surface slow enough to survive would be a lot smaller than those
which can do this on Earth. Perhaps a few fragments of exploding larger
objects might cool and fall this way, but my impression is that Earth
would have more meteorites remaining intact on or somewhat impacted into
the surface than would be the case on Mars.
- Robin
More information about the Meteorite-list
mailing list