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Take a minute from your hectic rushing around and see if you can stand or sit very still. How fast would you say you are going? You probably think that you aren't moving at all, and your body seems to be at rest. But that's just because your body is moving at exactly the same speed as the ground underneath it, and today I want you to consider the many ways and the fantastic speeds that you and I, and everyone else, are moving, even when we think we are standing still.

This is one of the methods I use to get children to think about the wonders of the universe, and to see their own planet as being nested in larger and larger systems, rather like a set of huge Russian eggs that fit inside each other.Let's look first of all at the speed at which our planet is revolving. The Earth spins on its axis (the imaginary line connecting the North and South Poles) once every 24 hours, and during that time, anyone living at the equator travels the distance around the Earth at the equator: approximately 25,000 miles. Therefore, they are traveling at a constant speed of 25,000 miles in 24 hours, or a little more than 1,000 mph.

The distance around the Earth gets smaller as you move away from the equator, so the nearer to the poles you live, the less distance you'll travel during each rotation, and the slower your speed will be. People who live in Florida or southern Texas, for example, are whirring around at about 900 mph, while those in Anchorage, Alaska, are going only about 500 mph. And at the North Pole? Well, there your speed would be 0.

But wait a minute. This Earth we are riding on is not only spinning on its axis, it is also flying through space as it orbits the sun. Each year our planet travels 584 million miles in its orbit around the sun, and so all of us, no matter where we live, are cruising around this loop at an average speed of 18.5 miles every second, or 66,600 mph. But there's more.

Not only is our planet in motion, but so is our solar system. All nine planets, and all their moons, and our sun are moving together in space. Astronomers have noticed that the stars near Vega (the third brightest star in the sky) and those in the constellation Hercules seem to be moving away from one another, and they reason that this is because we are moving closer toward them. Our solar system, therefore, is moving in the general direction of Hercules, and scientists have measured the speed of this movement to be about 12 miles every second - that's another 43,000 mph. Brace yourself, there's still more.

Our sun is just one of billions of stars that make up the galaxy known as the Milky Way. This galaxy seems to be in the shape of an incredibly huge disc or saucer, and we live about two-thirds of the way out from its center. The entire galaxy is turning or spinning like a wheel, and it makes one complete revolution every 200 million years. The farther away from the center you happen to be, the greater distance you will travel during those 200 million years, and so the faster your speed will be. The best estimate we can make about our own speed of rotation is more than 500,000 mph.

But our Milky Way appears to be doing more than rotating. In fact, all the galaxies (and there are millions that we know of) appear to be moving away from each other at speeds that approach the speed of light.

Whew! I'm dizzy just thinking about this. I better sit down for a little while and try to stay very, very still.- Dr. William F. Russell's books for parents and children include "Classics to Read Aloud to Your Children" and "Classic Myths to Read Aloud." Send your questions and comments to him at Family Learning, 2400 E. Main Street, Suite 266, St. Charles, IL 60174-2414.