Explanation:
Was the oldest known rock on Earth found on the Moon?
Quite possibly.
The story opens with the
Apollo 14 lunar
mission.
Lunar sample
14321, a large rock found in
Cone crater by astronaut
Alan Shepard, when analyzed back on Earth,
was found to have a fragment that was a much
better match to Earth rocks than other Moon rocks.
Even more surprising,
that rock section has recently been dated back
4 billion years,
making it older, to within measurement uncertainty, than
any rock ever found on
Earth.
A leading hypothesis now holds that an ancient comet or
asteroid impact launched
Earth rocks into the Solar System, some of which fell back to
the Moon,
became mixed with heated lunar soil and other rocks, cooled, and re-fragmented.
The video features an internal
X-ray scan of
14321
showing multiple sections with markedly different chemistries.
Moon rocks
will continue to be
studied to learn a more complete history of the
Moon,
the Earth, and the
early Solar System.
Friday marks the
50th Anniversary of the
Apollo 14
landing on the Moon.
