A Spherule from the Earths Moon
Explanation:
How did this spherule come to be on the Moon?
When a
meteorite strikes the Moon, the
energy
of the impact melts some of the
splattering rock,
a fraction of which might cool into tiny
glass beads.
Many of these
glass beads
were present in
lunar soil samples returned to Earth by the
Apollo missions.
Pictured above is one such glass
spherule
that measures only a quarter of a
millimeter across.
This
spherule
is particularly interesting because it has been victim to an even smaller impact.
A miniature
crater is visible on the upper left, surrounded
by a fragmented area caused by the
shockwaves of the
small impact.
By
dating
many of these
impacts,
astronomers can estimate the history of
cratering on our Moon.
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.