
Mysterious White Rock Fingers on Mars
Credit: G. Neukum (FU Berlin) et al., Mars Express, DLR Mars Express
Explanation: What caused this unusual white rock formation on Mars? Intrigued by the possibility that they could be salt deposits left over as an
ancient lakebed dried-up, detailed studies of these fingers now indicate that this is not correct. The light material appears to have eroded away from
the surrounding area, indicating a very low-density composition, possibly consistent with volcanic ash or windblown dust. The stark contrast between
the rocks and the surrounding sand is compounded by the sand's unusual darkness. This picture was taken from the Mars Express spacecraft currently
orbiting Mars. Planetary scientist Emily Lakdawalla, among others, has followed her curiosity about this unusual Martian landform into a fascinating
investigation that is eloquently described in the Planetary Society Weblog. The mysterious white rock spans about 15 kilometers across inside a larger
crater that spans about 100 kilometers.

I'm in denial and still think it's salt, but but then it would be a precipitate from a water solution. So halobateria?
[edit on 4/23/2008 by die_another_day]