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The Perseid meteor shower is an annual event occurring Aug. 12 to 13 this year, with peak activity anticipated on Sunday night. The shower is the result of debris from the Swift-Tuttle comet that falls through our atmosphere creating a streak of light.
Shannon Schmoll, director of the Abrams Planetarium and professor in the Department of Physics and Astronomy in the College of Natural Science at Michigan State University, explains why the upcoming Perseid meteor shower is a great opportunity to see an object from space closer than usual — at a safe distance and with your naked eye.
What is a meteor and meteor shower?
A meteor is a piece of rock or dust that ends up falling through our atmosphere. The friction generated when the material burns up in our atmosphere causes it to shine briefly. Meteor showers are regular events that result from Earth passing through a known debris field that crosses our orbit.
Why is the Perseid meteor shower unique?
The Perseid meteor shower is one of the better meteor shower shows each year with one of the higher meteors-per-hour rates. Also, many of the other meteor showers that have good rates tend to occur in winter. So, this is one of the best shows to see in warmer months.
You don’t need a telescope to see it either, which is a special treat. Also, so much of what we study in astronomy is so far away. The scales of space are not ones we can easily fathom in our everyday life. Meteors are a good reminder that we are a part of something larger, and meteor showers like this are one of the few ways we really have contact with things beyond Earth.
How many meteors can I expect to see?
The measurement used to describe the number of meteors you see per hour is called the Zenith Hourly Rate, or ZHR. This represents how many meteors you could see under the darkest conditions assuming the shower is radiating from the highest point in the sky, which is not possible. Therefore, the ZHR is always a much bigger number than is possible to see while sitting outside. Most meteor shows are a ZHR of 5 or less. The ZHR for this year’s shower is 100, which is fairly typical for the Perseids. That is pretty high, so even without ideal circumstances, you will likely see one meteor every couple of minutes or so if you can get to dark skies away from city lights early in the morning hours. That, combined with the moon rising late and not being as illuminated, makes this a pretty good viewing year.
Where should people go for the best view? Any tips?
You can look anywhere in the sky. The meteors will appear to radiate from a point in the northern sky from the constellation Perseus — hence the name. It is best to get as far away as possible from any light pollution, be patient and try viewing the shower in the early hours of the morning before sunrise.
It’s important to note that, because the ZHR does fluctuate annually, this year’s rate is pretty good. Additionally, the moon is in a crescent phase that doesn’t rise until almost 4 a.m. during the shower’s peak. This means there will be less light from the moon to interfere with seeing the meteors streak across the sky.