Predicting Weather By The Moon - Xavier University Libraries

Weather By The Moon
about 2,903 miles from the centre of the Earth? Or did the
Moon form out of initial cloud of gas and dust at the same
time and same place as the parent planet?
The current theory is that third possibility, that of
co-formation, much weight being given to the fact that both
Earth and Moon seem to be the same age. It seems that the
solar nebula, the beginning of moons-to-be (called protomoons)
draw material to themselves from the cloud of gas
and dust around them. Because of the extreme cold of space,
this theory seems to explain the many icy moons around
the giant planets in the outer solar system.
The temperature difference which plays a role in the
formation of the planets seems also to play a role in the
formation of their moons. Just as the planets became more
and more icy the further from the sun, moons seem to be
more and more icy the further from the planet they orbit.
For example, Jupiter’s moon Io (close to Jupiter) is very
rocky, but Europa (farther from Jupiter) has more ice,
Ganymede and Callisto (further still from Jupiter) have lots
more ice.
By whatever means it came to be in place, as Earth’s
Moon finished forming, about 4.5 billion years ago, the
surface was hit by the remains of the boulders which are
thought to have formed the Earth. During this time the
Moon warmed and experienced volcanism. There is abundant
evidence of volcanic plains from this time period.
Toward the end of the period of bombardment by boulders,
scientists think that the Moon was hit by a series of very
large boulders, these collisions forming what we know to-
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