In the meantime, NASA can look for new craters made by objects too small to detect while still in solar orbit.
NASA Briefing: NASA Images Suggest Water Still Flows in Brief Spurts on Mars
NASA | 6 December 2006
Posted on 12/06/2006 1:46:00 PM EST by bd476
http://www.freerepublic.com/focus/f-news/1749378/posts
http://www.nasa.gov/mission_pages/mars/images/pia09020.html
[snip] The first fresh impact site, shown on this page, was first noticed on Jan. 9, 2006, in an image acquired three days earlier. The image was acquired by the wide-angle camera at its highest possible spatial resolution, about 240 meters (262 yards) per pixel. To the northwest of the area imaged by the narrow-angle camera, the red, wide-angle context frame showed a dark spot. This spot was not present in any previous image acquired by any spacecraft, from Mariner 9 (which arrived in 1971) on down through Mars Express (which arrived in 2003). [end]
A big, fresh crater that has punched through and excavated a thousand feet deep perhaps through permafrost layers would do a lot more than these little five foot craters that merely stir up the dry dust.