Mars soil proves indigestible?
http://phoenix.lpl.arizona.edu/news.php
http://www.unmannedspaceflight.com/index.php?showtopic=5199&st=30
Won't pass through the screening filter, apparently. We knew the stuff was clumpy, but this seems to be a bit of an issue.
Ah well, I'm sure with time they'll get something through...
