Earth-bound studies point out places for future Mars missions to seek subsurface water (Forwarded)

Arkansas Center for Space and Planetary Sciences
University of Arkansas
Fayetteville, Arkansas

Contact:

Derek Sears, W.M. Keck Professor of Space and Planetary Sciences
Director, Center for Space and Planetary Sciences
J. William Fulbright College of Arts and Sciences
(479) 575-7625

Kathryn Bryson, Center for Space and Planetary Sciences
J. William Fulbright College of Arts and Sciences
(479) 575-3170

Daniel Ostrowski, Center for Space and Planetary Sciences
J. William Fulbright College of Arts and Sciences
(479) 575-3170

Melissa Lutz Blouin, director of science and research communications
University Relations
(479) 575-5555

3/15/2007

WHAT LIES BENEATH

Earth-bound studies point out places for future Mars missions to seek
subsurface water

FAYETTEVILLE, Ark. -- Studies conducted by University of Arkansas
researchers suggest locations where future Mars missions might seek liquid
water underneath Martian soil.

Graduate students Kathryn Bryson and Daniel Ostrowski, postdoctoral
researcher Vincent Chevrier and Derek Sears, director of the Arkansas Center
for Space and Planetary Sciences, will present their findings Friday, March
16, at the Lunar and Planetary Sciences conference in Houston.

The researchers used a planetary environmental chamber to simulate
conditions found on Mars -- a carbon dioxide atmosphere, 7 millibars of
pressure and temperatures near zero degrees Celsius. Bryson looked at the
evaporation rates of ice buried beneath fine-grained basaltic soil at depths
of 2.5 to 50 millimeters.

"Soil layers only 5 millimeters deep slowed the evaporation process and
greatly increased the lifetime of an ice layer," Bryson said. A soil barrier
on top of an ice layer can enable the formation of liquid water by slowing
the evaporation rate and warming the surface.

Ostrowski examined the evaporation rates of ice beneath montmorillonite, an
aluminum-rich clay recently shown to be present on Mars. Montmorillonite is
a hydrated clay that requires the presence of water in some form for its
creation.

Studies of the clay soil indicate that the diffusion rate doesn't become
steady as quickly as other non-clay materials do, possibly indicating that
the clay is adsorbing water, either in liquid or gas form.

"This does not directly imply liquid water, but it does give the possibility
if the conditions are right," Ostrowski said.

The upcoming Mars Phoenix Lander mission will be looking for environments
similar to those investigated in these experiments, and scientists hope to
find evidence for water -- and possibly life -- in these regions.

The Arkansas Center for Space and Planetary Sciences is a joint center in
the J. William Fulbright College of Arts and Sciences and the College of
Engineering.

For information, please see
http://spacecenter.uark.edu