What makes Earth keep spinning?

Hello toxic0n,

The following web page provides a good answer to the question, "What
makes the Earth keep spinning?" or, to phrase it another way, "Why
does the Earth spin?"

"Dear Dr. Universe -- Why does the Earth turn?"
Ask Dr. Universe [Washington State University]
http://www.wsu.edu/DrUniverse/earth5.html

The short answer to why the Earth keeps spinning is angular momentum
(as discussed in the article cited by pinkfreud) and the lack of
forces that would slow the spinning significantly (although some
forces do slow it a little).  The page I've cited provides a more
detailed answer.

- justaskscott


Searched on Google for:

"why does the earth"
"what makes the earth"

This may be helpful:

http://www.suite101.com/article.cfm/astronomy/54640

Many people say the gravity of earth is what makes it spinning.
Although the source of the energy or power which gives it the power
has not been yet found if this power stops working for a second, world
may be in a big danger of destruction. You would see many rumors about
world to stop spinning in a period of time, but nobody knows if it?s
true or not. If you look at this from a religious point of view, then
you may find the answer that God is spinning the Earth. And can stop
it form spanning at any time. Scientifically, many scientists still
haven?t found many of the secrets behind the earth and it?s past.
Earth is full of questions like this and many of them have no specific
answer to them but a few opinions. I hope my opinion works
Harris.

the earth is slowing down . . . which is why we have a leap second. 

http://tycho.usno.navy.mil/leap.html

http://www.boulder.nist.gov/timefreq/general/leaps.htm#Anchor-52904

A leap second is a second added to Coordinated Universal Time (UTC) to
make it agree with astronomical time to within 0.9 second. UTC is an
atomic time scale, based on the performance of atomic clocks.
Astronomical time is based on the rate of rotation of the earth. Since
atomic clocks are more stable than the rate at which the earth
rotates, leap seconds are needed to keep the two time scales in
agreement.

The first leap second was added on June 30, 1972, and they occur at a
rate of slightly less than one per year, on average. Although it is
possible to have a negative leap second (a second removed from UTC),
so far, all leap seconds have been positive (a second has been added
to UTC). Based on what we know about the earth's rotation, it is
unlikely that we will ever have a negative leap second.

I just remembered something. The earthquake that caused the Asia
Tsunami was so large that if make the earth smaller (in diameter)
therefore speeding it up a bit. (like a ice skater pulling in her
arms)

Perhaps you want a very simple answer. Anything which is moving
continues moving unless something stops it. This includes rotational
movement, like the Earth.

Best

As planets during their formation attract more mass, their spinning
becomes faster, comparable to a balletdancer who bends the arms
towards the body. Energy is conserved and the angular momentum of a
dancer is lost due to friction. Look at earth as a dancer with a core
of different nature and density which therefore spins at a different
speed and creates this typical magnetic field. As the spin of the
outer layer slows, the inner core will reach a moment at which its
spinning reverses, explaining pole shift.The spin of the outer layer
has to slow down, simply because earth looses energy under different
forms, mostly as radiation and magnetism, and indeed it shrinks. The
initial momentum of the ballet dancer is explained by a kick of the
legs, for matter as earth an initial spin is intrinsic, due to the
core nature of the smallest matter we know which up to now dictates
that everything turns around something, which is energy in its purest
idea.