Chicken Little Right: The August Sky Is Falling!
Last updated 9/14/2023 at 11:43am
Few sights are as thrilling as the fiery spectacle known as a falling star, also called a shooting star or meteor. Astronomers cannot predict exactly when or where a meteor will appear, but each year during mid-August, skywatchers head away from the city lights to view one of the year's most reliable displays: the Perseid meteor shower.
This year will be no exception; the shower's peak is expected to occur during the night of Saturday, Aug. 12, and the early morning hours of Sunday, Aug. 13, but stargazers will surely spot a few meteors from this shower for a week or so before and after this date.
While they may appear quite stunning, meteors are not all that uncommon. Our region of space is littered with dusty particles called "meteoroids," most no larger than a sand grain. As one falls into our upper atmosphere at more than 100,000 miles per hour, it disintegrates in a quick, but dramatic, burst of light. A conscientious observer can typically see three or four random (or "sporadic") meteors every hour falling from various directions on any clear night.
There are times when our chances of seeing meteors improve, however, and mid-August is one of them. That's because our planet will be carrying us on our annual journey through the swarm of dusty debris expelled by the slowly disintegrating comet Swift-Tuttle.
After watching for a while, you'll notice that these meteors can appear anywhere in the sky, but if you trace their paths backward, you'll discover that the meteors coming from the Perseid swarm appear to radiate from one location in the sky.
This point is called the shower's "radiant" and is often named for the constellation in front of which it appears.
This is why the August shower is known as the Perseids: Its radiant lies in the direction of the constellation Perseus, now in the northeast. Any meteors that radiate from elsewhere are sporadic meteors – random flecks of dust not part of the Swift-Tuttle swarm.
So why do astronomers always suggest that you will see more meteors before dawn? It's quite simple, really. The phenomenon is similar to a car encountering a swarm of bugs on the highway. Since our car is moving into this swarm, our windshield receives the brunt of the impacts, while the side and back windows hardly get any. So it is with meteor showers.
Our best view often comes when we're peering in the direction of our orbital motion, and that comes before dawn. This August, the waning crescent moon will appear in the early morning sky, but its light won't be much of a hindrance.
For the best view, you might like to camp in the mountains, deserts or countryside, or set up on side rural roads away from traffic. No special equipment is required either; all you need to enjoy the sky show is your eyes, but binoculars could be fun to check out long trails left behind by any exploding fireballs. Be sure to take a lawn chair or sleeping bag and a blanket or hot chocolate to keep warm – yes, even in the summer – as you gaze skyward.
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