Layered Hills on Mars
Explanation:
Why are some hills on Mars so layered?
The answer is still under investigation.
Clearly,
dark windblown sand
surrounds outcropping of light
sedimentary rock across the floor of crater
Arabia Terra.
The
light rock
clearly appears structured into many
layers, the lowest of which is likely very old.
Although the
dark sand forms dunes, rippled dunes of
lighter colored sand are easier to see surrounding the stepped
mesas.
Blown sand
possibly itself eroded once-larger mesas into the layered hills.
Most of the
layered shelves
are wide enough to drive a
truck around.
The
above image, showing an area about 3 kilometers across,
was taken in October by the
Mars Global Surveyor spacecraft currently orbiting
Mars.
Tomorrow, the
first of three
robot spacecraft from Earth is scheduled to arrive at the
red planet.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
