A washed-out meteor shower, but a fantastic celestial hugging instead
It’s time once again this year for the Perseid meteor shower, and most years, it’s a marquee stargazing event over Butler, but not this year. You can blame it on the moon, which will be washing out most of the “shooting stars” of the Perseids. The Perseids peak on Wednesday morning after midnight, but at the same time, the heavens will also be filled with a bright waning full moon that’ll visually wash out the sky, even in the countryside. For sure, you’ll still see some meteors, but many of them will be lost in the moonlight bath. In years when the moon isn’t a factor, you may see over 50 meteors an hour. You may see only about half as many this year or fewer.
Meteor showers occur when the Earth, in its orbit around the sun, runs into a trail of small debris left behind by a comet. Comets are mainly dirty snowballs of ice with embedded debris that, for the most part, have highly elongated orbits that take them from the far outer regions of our solar system to the inner neighborhood near the sun. As they swing close to our home star, the dirty snowballs at least partially melt, liberating and littering small bits of debris, usually ranging from dust grains to pebble-sized.
As Earth swings into these debris trails, the debris gets gravitationally sucked into its atmosphere and burns up. The meteors are slamming into our atmosphere with speeds as high as 44 miles per second. Much of the light streaks that we see as meteors are not so much because of incineration but rather the temporary atomic destabilizing of the column of air they’re coming through.
Even though the Perseids will be “moonwashed” out this year, it’s still a lot of fun to lie back on a reclining lawn chair, roll your eyes all around the sky, and see how many meteors you can spot. Again the best time to watch for them will be Wednesday morning from about midnight to the start of early morning twilight. You’ll probably also catch a few falling stars on Monday and Tuesday morning as well. There’s a great app called NightCap that turns your smartphone into an astronomical camera. It costs around $3, but it is so worth it. It has a mode that allows you to take a photo of any part of the sky, and it detects and photographs meteors. It’s wonderful!
While you’re out in that lawn chair trying to view the diminished Perseid show, there’s going to be a fantastic celestial conjunction, or what I like to call a celestial hugging between the very bright planets Jupiter and Venus in the predawn hours of Aug. 12. Moonlight will have no effect on the spectacle. It should be a stunning site! About a couple of hours before sunrise they’ll rise together above the eastern horizon less than a degree apart. That’s less than the width of your finger held at arm’s length. They’ll resemble cat’s eyes, although Venus will be much brighter than Jupiter. You’ll be able to see Venus and Jupiter, along with Jupiter’s moons, in the same field of view with binoculars or a small telescope. You can also capture a wonderful image of the planets using a smart photographic telescope, such as the ZWO SeeStar 50 or SeeStar 30.
Both planets will still be visible well into morning twilight before fading out as sunrise approaches. Obviously, both planets are not physically close together but are nearly in the same line of sight. It’s a lot of fun if you get a chance to watch the two planets approach each other in the early morning hours leading up to Aug. 12. Next week on Aug. 19 and 20, as the planets separate from each other, the waning crescent moon will be close by. That’s worth setting the alarm for!
Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO Radio in Minneapolis/St. Paul. He is also the author of “Stars: a Month by Month Tour of the Constellations,” published by Adventure Publications and available at bookstores and at adventurepublications.net. Contact him at mikewlynch@comcast.net.
