We often speak of the Sun and Moon crossing the sky, but of course, what we are actually experiencing is the effect of the Earth’s rotation which propels us from west to east at around 1000 kilometers per hour (at our latitude). It’s a good thing my fridge is also rotating at that speed, or I’d never get to eat.
However, both the Sun and Moon are in fact in motion as well, as is everything else in the universe.
The Moon is whipping along at about 3,700 kmph; you can actually see that motion against the background stars over the course of a few hours. Then, of course, the Earth orbits the Sun at 108,000 kmph. The Sun then drags its planetary family along as it orbits within the Milky Way galaxy at around 800,000 kmph, Topping it off, the galaxy itself sets the speed record, zipping along through space at a jaunty 2.1 million kmph.
With all this going on simultaneously in all kinds of directions, it is a mystery why every day is not a bad hair day.
All this motion is, in fact, necessary. If it were to stop, gravity would take over, and everything would be attracted to everything else, making for one large reunion in the middle. In fact, that may be happening on a larger scale. Our galaxy does not appear to be orbiting anything; it, and most of the other nearby galaxies, appear to be headed toward a gravity anomaly called the Great Attractor, which is in turn moving toward something bigger. Stay tuned.
All very nice, you may say, but how can a bunch of astronomically big numbers (pun intended), or even backyard astronomy itself, help me in everyday life? Well, the possibilities are endless.
For example, if you are ever pulled over for speeding, you would be scientifically correct to point out to the officer that every time you get in your car, you are in fact constantly speeding in every direction, and that singling out your insignificant highway infraction on that day could be seen as being really petty on their part.
Feel free to print off this article to use in your court appearance. And, on this one occasion, it might also be prudent to avoid mentioning that sometimes you stand around in the dark with binoculars.
