Seasonal Streaks Point to Recent Flowing Water on Mars
Explanation:
What creates these changing streaks on Mars?
Called Recurring Slope Linea (RSL), these dark features start on the slopes of
hills and craters but don't usually extend to the bottom.
What's even more unusual is that
these streaks appear to
change with the season,
appearing fresh and growing during warm weather and disappearing during the winter.
After
much study, including a
recent chemical analyses, a leading hypothesis has emerged that these streaks
are likely created by
new occurrences
of liquid salty water that evaporates as it flows.
The source for the briny
water
is still unclear, with two
possibilities being condensation from the Martian atmosphere and underground
reservoirs.
An exciting inference is that if these
briny flows are not too
salty, they may be able to support
microbial life on Mars even today.
The featured image of a hill inside
Horowitz Crater
was investigated by instruments aboard the robotic
Mars Reconnaissance Orbiter
that has been returning data from Mars since 2006.
Retrospective:
Today in
APOD History
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
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rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
