Will The Earth Stop Rotating?
Date: 1999 - 2000
Will the earth stop rotating?
Yes, but not for a long long long time. (If I remember correctly, it is
currently slowing down by about half a second per century.) As the
earth rotates it gets stretched and squeezed by tidal forces. The
energy required to do this work comes from the earth's rotation.
The simple answer to this is No.
It is believed that the Earth's day will be twice as long as it is now, in
about 5 thousand million years time, but there is too much momentum in the
Earth to stop it from rotating.
By the way, at the moment the Earth is rotating its fastest since the late
1920s, having lost approximately 0.63 milliseconds per day in the last 12
months (to June 28, 2001) against atomic time, based on preliminary
International Earth Rotation Service data; compared with 3.13 milliseconds
per day in 1972, and 3.89 milliseconds per day in 1912. The Earth GAINED on
atomic time in 1929 by 0.35 ms/day.
Because of tidal friction.... yes it will. In fact, it is slowing as
we ride on it now. Actually, it will not stop, but rather the period of
rotation will equal its period of revolution. I do not have the number
at hand, but I seem to recall that each (solar) year is .00024 seconds
slower than the year one century earlier. The number may not be
correct, but the concept is. In the same way that the moon has rotates
around the earth, the earth will eventually rotate around the sun... if
the sun does not supernova first!
There is a small tidal drag on the earth caused by the gravitational
forces of the moon and sun which have a small effect on the earth's
rotation, but the effect, while measurable, is exceedingly small. On the
other hand, the reason the moon always presents the same face to the earth
it is believed was caused by tidal drag of the earth on the moon, which is
much greater because the mass of the moon is so much smaller than that of
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Update: June 2012