Don't bother staying up for Perseid shower
Just like clockwork, it's time once again for the Perseid meteor shower, usually one of the best meteor showers of the year. The Earth, in its orbit around the sun, is driving into a trail of debris left behind by comet Swift-Tuttle. The peak of the shower is the night of Aug. 12 and the morning of Aug. 13.
The Perseids are the Old Faithful of meteor showers and normally you can see more than 60 meteors per hour in the dark skies of the countryside. Unfortunately, the moon will spoil the shooting star party this year. During the peak of the shower on Aug. 12, we'll have a waning near-full moon that will rise a little after 9:30 p.m. and light up the remaining hours of the night. Most of the meteors will be washed out in all that moonlight. To be honest with you, I wouldn't go to a lot of trouble to watch the Perseids this year, but if you're somewhat away from the city lights, you'll see a few shooting stars, especially after two or three in the morning.
It's called the Perseid meteor shower because all of the meteors seem to be streaming from the constellation Perseus in the northeastern sky. Now that doesn't mean that all of the meteors will be restricted to that part of the sky. You'll actually see shooting stars all across the sky, but their trails will all point back in the general direction of Perseus.
No need for a hardhat with the Perseids because 99.999 percent of these meteors are no larger than grains of dust that quickly burn up as they slam into our atmosphere at speeds over 40 miles per second. Most of the light that you see from the meteors is caused by these fast-moving particles temporarily ionizing the atoms and molecules in the column of air they are ripping through.
Even though the Perseids are kind of a bust this year, there's still a great show going on in the early morning eastern sky. The bright planets Venus and Mercury will be in a close celestial hug, known more formally as a conjunction. Look for the brightest starlike object in the low eastern sky between 5:30 and 6 a.m. on Aug. 13. You can't miss Venus. Just below Venus you'll see a smaller, fainter star which is actually Mercury, the closest planet to the sun. The two planets are only two degrees apart from each other and will hang by each other through this week and into the next. Later on this month, around Aug. 20, there will be a spectacular early morning conjunction of three planets: Mercury, Venus, and Saturn. I'll have more on that later this month in Skywatch.
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis and author of the book, "Pennsylvania Starwatch," available at bookstores and at his Web site www.lynchandthestars.com.
