By DAVID WARD
August is that perfect month for stargazing when the nights are still delightfully warm, darkness comes at a more reasonable hour and shooting stars blaze across the nighttime sky.
The biggest attraction this month up above is the “Old Faithful” of meteor showers, summer’s grand shooting star show, the Perseid meteor shower. They are called the Perseids because they seem to originate from the constellation Perseus, located in the northeast sky this time of year. Of course, they are not stars at all but rather tiny bits of dust and debris left over from comet Swift-Tuttle, which orbits our sun every 130 years or so.
These little bits of sand-sized particles hit our upper atmosphere at a speed of 37 miles per second and heat up instantly due to friction, and ionize a column of air which is what we see as a “shooting star.”
This month will be a great showing for the meteor shower because the moon will be mostly out of the way. A bright moon will outshine the fainter stars and a lot of meteors. You will be able to see more shooting stars than normal for a couple of weeks during mid month, but the peak of the show will be on the nights of Aug. 11-12 and Aug. 12-13. For optimum viewing, the later in the evening the better.
After midnight our side of the Earth will be headed into the meteor stream. Imagine driving your car into a snowstorm at night. More snowflakes will hit the front windshield than the rear. After midnight our “front windshield” will be headed straight into the oncoming meteors.
Watching a meteor shower is about the easiest stargazing activity there is. You do not need a telescope or even binoculars and you do not need to know any of the constellations or worry about how to tell the difference between a planet and a star. Just lie out on a mat or chaise lounge and look up. What could be simpler?
The meteors could be anywhere in the sky but if you trace their paths back, they will be coming from the northeast. One of the cool things about the Perseid shower is that it produces more spectacular fireballs than any other meteor shower. If you are lucky you might see something really awesome streaking across the heavens.
Shooting stars are tiny, the size of a grain of sand or less, and they are close, only a few tens of miles up. Want to see something big, really big? Look right up overhead for a dim band of light stretching from horizon to horizon, from the north to the south. It does not look really dramatic, like a wisp of a cloud perhaps, but it is big, and I mean beyond big. It is about the most enormous thing you can see up there. That is our home in the infinite cosmos, the Milky Way Galaxy. Astronomers estimate it to be about 600,000,000,000,000,000 miles across and that is a bit larger than the grain of sand-sized meteors streaking overhead!
The light from that dim glow is actually coming from billions of suns that are so far away that their light has been traveling for thousands of years across an unimaginable vast void of space to reach your eyes.
Hanging out with us in our home are an estimated 200 billion to 300 billion other suns, probably a greater number than that of planets, and giant clouds of hydrogen gas that our little solar system would get lost in. But all that only makes up about 10 percent of our Milky Way Galaxy. The other 90 percent is the mysterious “dark matter” and nobody has a clue what that is!
Here are a few other things to look for up there. Saturn is sort of low in the southwest, a fairly bright yellowish-looking object that does not twinkle like the stars. Venus can be seen low in the west just after sunset and it is really bright. If you are up early on Aug. 3, look low in the east at dawn for a crescent moon very close to bright Jupiter with dimmer Mercury and Mars below. On Aug. 9 look for the crescent moon close to Venus in the west just after sunset. On the evening of Aug. 12, join me up at Sun Mountain Lodge for the meteor shower and other celestial wonders. Hope to see you there!