How does the Earth move?

"Why does the earth move around a lot?" asked a Schaumburg Public Library summer science fan.

The Earth is always on the go. It makes one complete rotation a day, meaning that it turns a full circle every 24 hours (to be exact, it's once every 23 hours, 56 minutes and 4.09053 seconds, called the sidereal period).

The speed of the rotation varies depending on where the measurements are taken. The fastest orbital speed is at the equator clocking in at 1,000 miles per hour. There's no speed at either pole.

The Earth swaggers; it's on a tilt, what scientists call a wobble or precession, first identified by Sir Isaac Newton about 350 years ago. Scientists say shifting ice sheets cause the swing.

The wobble took a large shift about 20 years ago, leaving scientists with a new puzzle to solve. Initial conclusions are that melting ice in Greenland and Antarctica, compounded by a drought in the Caspian Sea and in India, are changing the surrounding land masses, forcing the wobble to switch prematurely. With today's climate warming occurring at such a fast pace, more unpredicted wobbles could occur.

Internal forces like earthquakes and tsunamis can rev up the Earth's rotation speed. Japan's 8.9-magnitude earthquake and resulting tsunami in 2011 actually increased the Earth's spin speed, shortening the earth's day by 1.8 microseconds. Other natural forces like the jet stream and El Nino can either increase or pump the breaks on the Earth's speed.

The Earth's no slacker. As it rotates, it orbits the sun. One full revolution takes 364¼ days. The total eclipse in August was a reminder of the Earth's orbit around the sun and the moon's orbit around the Earth. The Earth jogs through this journey at 67,000 miles per hour. It orbits the sun in a circular path that changes to an oval path every 100,000 years. This is called the Earth's eccentricity.