Unusual Spherules on Mars
Explanation:
What are those unusual spherules on Mars?
The
Mars Opportunity rover
has now photographed several unusual nodules on Mars that
have a nearly spherical shape.
Many times
these spherules are embedded in
larger rock outcroppings but appear grayer.
Pictured
in the inset is one such spherule embedded in a rock dubbed Stone Mountain, visible
to the
Opportunity rover now rolling
inside
a small crater on
Meridiani Planum.
Opportunity was directed to go right up to
Stone Mountain to get a better look.
The
inset
picture spans only 3 centimeters across, revealing the rock to be named more
for shape than actual size.
Scientists are currently debating the origin of the
spherules.
One leading hypothesis holds that the
beads were
once-molten rock that froze in mid-air after an
impact or a volcanic eruption.
Another hypothesis holds that the spherules are
concretions, hard rock that slowly accumulates around a central core.
Opportunity will work to solve this mystery and others over the next few days.
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.
