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NASA Details Earthquake Effects on the Earth
Cuyamaca writes "
NASA
scientists, using data from the Indonesian earthquake
calculated it affected Earth's rotation, decreased the
length of day, slightly changed the planet's shape, and
shifted the North Pole by centimeters. The earthquake that
created the huge tsunami also changed the Earth's rotation." You now have 2.68 fewer microseconds each day to do whatever it is you do.
The earths rotation has been temporarily increased. It will slow down to normal over the period of about 100 days.
Angular momentum is conserved and is calculated by L = Iw where I is the rotational inertia, w is the angular velocity and L is the constant product. So if I goes up (and I will show in a minute how that happens), w must go down. I, the rotational inertia, is calculated different ways for different geometries. A long stick held by the end has a larger I than the same stick held by the center, for instance. Another example is a sphere, like the Earth, rotating on an axis. If it suddenly puts out a long arm, that's going to increase its rotation inertia considerably, decreasing its angular velocity. Lifting up a whole region by a few inches could easily do that.
(...) This millisecond change
Microsecond change. Adds up to a second in 1000 years.
bjd
(...) I lose 2.68 seconds every 2737.9257 years.
Check your math.
bjd