Explanation:
Does this moon look familiar? Possibly not, even though it is Earth's Moon.
Locked in synchronous rotation, the
Moon
always presents its well-known near side to Earth.
But from lunar orbit,
Apollo astronauts
also grew to know the Moon's far side.
This
sharp picture from
Apollo 16's
mapping camera shows the eastern edge of the
familiar near side (top)
and the strange and heavily cratered
far side of the Moon.
Surprisingly, the rough and
battered surface of the far side
looks very different
from the near side which is covered with
smooth dark lunar maria.
The likely explanation is that the
far side crust is thicker,
making it harder for molten material from the interior to flow to the surface and form the
smooth maria.
