Predicting Weather By The Moon - Xavier University Libraries

Formation of the Moon
so, then the month, or time taken for it to orbit the Earth,
would have been a mere 6.5 hours. The tides raised by the
two bodies upon each other would have been violent indeed.
Yet the Moon would have suffered more from this
proximity. These mutual tides would have slowed down each
other’s axial rotations and pushed the Moon further away.
About 500 million years ago the Moon would already
have been 200,000 miles away, still with a bulge toward
the Earth which would have kept slowing the Moon’s
spin. Finally, the Moon would have stopped rotating altogether;
its revolution would have been 27.3 days, and the
Earth’s rotation would have increased to 24 hours.
The process is still continuing, because the Moon’s
tidal pull on the Earth is still slowing us down. Each day is
approximately 0.00000002 seconds longer than the day
before. This works out to a gain of one second in a hundred
thousand years, which only becomes noticeable when comparing
lunar eclipses observed many centuries ago.
Although the Moon is still receding from us it will
not keep receding indefinitely. At around 350,000 miles it
will start to come in again, due to the tidal effects brought
by the Sun, and then it will be broken up eventually by the
Earth’s gravtiational pull. It will end as a swarm of orbiting
particles around Earth in a system of rings like those of
Saturn. We would no longer have tides, except one big one
permanently aimed towards the sun. Life on Earth would
be impossible because there would be only atmosphere on
the Sun side of the Earth. There would probably be no water;
just one big stationary cloud.
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