When NASA says a celestial event is noteworthy, you know it should be spectacular.
That’s certainly the case with the Perseid meteor shower, which NASA calls “the best meteor shower of the year,” and is correspondingly the “most popular meteor shower,” according to the American Meteor Society (AMS).
Although the Perseid meteor shower is visible this year from July 14–September 1, it is expected to peak on August 12 and early on August 13. Stargazers can expect to see up to 100 meteors per hour traveling at 37 miles per second, NASA notes.
“With swift and bright meteors, Perseids frequently leave long ‘wakes’ of light and color behind them as they streak through Earth’s atmosphere,” NASA explains. “Perseids are also known for their fireballs, which are larger explosions of light and color that can persist longer than an average meteor streak.”
Why Meteor Showers Occur
Comets, which originate far outside the orbit of the outermost planets, have elliptical orbits around the Sun. For perspective, since they can be miles in diameter, NASA notes that they are about the “size of a small town.”
Comets are essentially a giant “dirty snowball” made of frozen gasses with embedded rock and dust particles, NASA continues.
As comets near the Sun during their orbit, they warm, freeing bits of rock and dust that are then left behind in what can be thought of as a trail of debris. Every year, when Earth passes through these trails of rock and dust on its own orbit around the Sun, the debris particles collide with Earth’s atmosphere.
When this happens, the particles heat up to temperatures of around 3,000 degrees Fahrenheit, creating streaks across the sky, Space.com explains. Those streaks, or shooting stars, stop abruptly when the intense heat evaporates most meteors.
The Perseid Meteor Shower’s Origin
The fragments of space debris that collide with Earth’s atmosphere to create the Perseid meteor shower each summer were left in the wake of a comet named 109P/Swift-Tuttle. The comet has a unique name because it was discovered in 1862 independently by both Lewis Swift and Horace Tuttle, NASA explains.
Swift-Tuttle is a large comet with a nucleus that is 16 miles wide. Amazingly, it takes 133 years for it to orbit the Sun.
Although meteor showers are caused by comet debris colliding with Earth’s atmosphere, they are named for their radiant — where they appear to come from in the night sky.
The Perseid meteor shower gets its name because its meteors appear to come from the constellation Perseus, named for the famed Greek hero. Perseus not only slew Medusa the Gorgon who had snakes as hair, he also rescued his future wife Andromeda from a sea monster sent by Poseidon to destroy the coast and land of Ethiopia.
How To Watch The Perseid Meteor Shower
Although the Perseid meteor shower’s peak will begin after about 10 p.m. local time on August 12, the best time to see the meteors will be before dawn the next morning. Indeed, the meteor shower is expected to reach peak activity at around 2 a.m. Mountain Time, 4 a.m. Eastern Time, on August 13, according to In The Sky.
In The Sky’s estimate calls for stargazers to see up to 138 meteors per hour, however, EarthSky’s estimate calls for stargazers to see 90 meteors or more per hour.
Finally, to really increase your chances of seeing meteors, you’ll want to be somewhere dark that is far away from city lights. You can use EarthSky’s map of dark places to find spots that are optimal for stargazing.
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