Sky Watch: As the world really turns

Did you ever have one of those days when nothing seems to move? No matter where you go -- the highways, the grocery store lines, even the ATM machine -- everything is at a standstill.

Happens way too often for my taste. So on days like this, I just wait until nighttime, step outdoors and gaze skyward. But wait, it looks like everything there is motionless, too.

Not so. The fact is that we on planet Earth are whirling through the cosmos in at least seven different directions at more than a million miles per hour. Some of the motions might be familiar to you; others may surprise you.

The Earth, of course, is spinning on its axis and carrying us in middle-northern latitudes at nearly 900 miles per hour.

But that's nothing compared to how fast we revolve around the sun -- 66,000 miles per hour. At that rate, each one of us had traveled some 583 million miles before celebrating our first birthday and nearly three billion miles before entering kindergarten. And over an average human lifetime, we will have crossed some 45 billion miles of space.

During the journey, however, our view doesn't change much; the stars are so distant that they appear to our eyes just as they did to our ancient ancestors.

Gaze high in the sky this week after dark and you'll find the famous asterism known as the Summer Triangle, composed of the bright stars Vega, Deneb and Altair. It is the star Vega toward which our sun and solar system are speeding at roughly 12 miles per second. No need to worry about a collision, though; even at this remarkable speed we'd need 5,300 human lifetimes to reach the star.

Even our Milky Way Galaxy is spinning like a giant Ferris wheel at nearly 140 miles per second, and it takes us some 220 million years to complete the two million trillion miles around the galactic center. Only two dozen times in the 5 billion year history of our planet have we passed this way; the last time, the first small dinosaurs were beginning to appear. The next? Who knows ...

Our Milky Way is also careening at 50 miles per second toward the Great Andromeda Galaxy, one of some 30 such structures that form a galactic family astronomers call the "Local Group" which, by the way, is falling toward the Virgo supercluster at another 150 miles per second.

And if that's not enough, beyond are even more galaxy superclusters as far as the largest telescopes can see. All are rushing away from each other as if hurled from a huge cosmic explosion some 14 billion years ago. Between these clusters glows the faint, ghostly echo of this primordial fireball through which we speed at more than a million miles per hour.

And what about the universe itself? Is it turning about an even larger universe? Is it speeding along in some unknown direction at an even more incredible speed? No one knows for sure, but it's certainly fun to ponder while we wait in yet another seemingly motionless line.

Hey, I'm next! Now where did I put that ATM card anyway ...