Perseid meteor shower: All you need to know in 2022
Early to mid-August meteors … the Perseids
Predicted peak: August 13, 2022, at 3 UTC.
When to watch: The moon will be up all night during 2022’s predicted* peak of the Perseid meteor shower. But this shower rises to a peak gradually, then falls off rapidly. And Perseid meteors tend to strengthen in number as late night deepens into the wee hours. The shower is often best before dawn. So, in 2022, from early August to mid-August, watch from late evening to dawn, until the waxing moon – brighter each night, and up for more hours – drives you back inside.
Duration of shower: July 14 to September 1.
Radiant: The radiant rises in the middle of the night and is highest at dawn. See chart below.
Nearest moon phase: Full moon falls at 1:36 UTC on August 12. There will be a bright moon up during the Perseids’ peak in 2022. Take advantage of the moon-free mornings in late July and early August for watching the Perseids (and the Delta Aquariids).
Expected meteors at peak, under ideal conditions: Under a dark sky with no moon, skywatchers frequently report 90 meteors or more per hour.
Note: The August Perseid meteor shower is rich and steady, from early August through the peak. The meteors are colorful. And they frequently leave persistent trains. All of these factors make the Perseid shower perhaps the most beloved meteor shower for the Northern Hemisphere.
The Perseids Parent Comet
The parent comet responsible for the Perseid meteor shower is a rather large comet called 109P/Swift-Tuttle. The comet orbits the sun approximately every 133 years. Lewis Swift of Marathon, New York, visually discovered it on July 16, 1862, using an 11 centimeter (3.5-inch refractor lens) telescope. He did not report it immediately, believing that he was observing Comet Schmidt, which was found two weeks prior. Then, three days later, Horace Tuttle picked it up from Harvard Observatory. Scientists calculated that the comet would return in 120 years. That is, that we would see it again in 1982.
So, 1982 comes and goes and the comet doesn’t show up. Oops! It was back to the drawing board, and this time, the appearance of a comet observed in 1737 was considered a possible early appearance of the comet. Now, the orbital period was more like 130 years. Brian Marsden published new orbital elements and an ephemeris as to where to find it as it comes back in 1992.
Many of us visual comet hunters would, from time to time, cover the part of the sky where the incoming comet was supposed to appear. The 1991 outburst of Perseid meteors indicated that the comet was probably on its way back. Another meteor outburst in 1992 seemed to confirm that.
On September 26, 1992, Tsuruhiko Kiuchi, an amateur astronomer and comet hunter, picked up the comet in the evening sky, just north of the bowl of the Big Dipper. Knowing where to look, I observed this comet 16 hours later and made a brightness estimate five times brighter than the original report. Others then confirmed this. Later, Gary Kronk suggested that the comets observed in 69 CE and 188 BCE were also appearances of this comet, a theory later confirmed.
Tonight, the comet is about 35 degrees south of the sun, and 42 times farther away than the sun. It is not visible in any telescope but will be visible in all telescopes, binoculars and to the unaided eye when it returns in the year 2126.
The beloved Perseid meteor shower
In the Northern Hemisphere, we rank the August Perseids as our all-time favorite meteor shower. The Perseids take place during the lazy, hazy days of northern summer, when many families are on vacation. And what could be more luxurious than taking a siesta from the heat of the day and watching this summertime classic in the cool of night? No matter where you live worldwide, the Perseid meteor shower will probably produce the greatest number of meteors on the mornings of August 11, 12 and 13.
Perseid meteor shower radiant point
If you trace all the Perseid meteors backward, they seem to come from the constellation Perseus, near the famous Double Cluster. Hence, the meteor shower is named in honor of the constellation Perseus the Hero.
However, this is a chance alignment of the meteor shower radiant with the constellation Perseus. The stars in Perseus are light-years distant, while these meteors burn up about 60 miles (100 km) above the Earth’s surface. If any meteor survives its fiery plunge to hit the ground intact, the remaining portion is a meteorite. Few – if any – meteors in meteor showers become meteorites, however, because of the flimsy nature of comet debris. Most meteorites are the remains of asteroids.
In ancient Greek star lore, Perseus is the son of the god Zeus and the mortal Danaë. It is said that the Perseid shower commemorates the time when Zeus visited Danaë, the mother of Perseus, in a shower of gold.
Comet Swift-Tuttle and the Perseids
Every year, from around July 17 to August 24, our planet Earth crosses the orbital path of Comet Swift-Tuttle, the parent of the Perseid meteor shower. Debris from this comet litters the comet’s orbit, but we don’t really get into the thick of the comet rubble until after the first week of August. The bits and pieces from Comet Swift-Tuttle slam into the Earth’s upper atmosphere at some 130,000 miles (210,000 km) per hour, lighting up the nighttime with fast-moving Perseid meteors.
If our planet happens to pass through an unusually dense clump of meteoroids – comet rubble – we’ll see an elevated number of meteors. We can always hope!
Comet Swift-Tuttle has a very eccentric – oblong – orbit that takes this comet outside the orbit of Pluto when farthest from the sun, and inside the Earth’s orbit when closest to the sun. It orbits the sun in a period of about 133 years. Every time this comet passes through the inner solar system, the sun warms and softens up the ices in the comet, causing it to release fresh cometary material into its orbital stream.
Comet Swift-Tuttle last reached perihelion – closest point to the sun – in December 1992 and will do so next in July 2126.
Bottom line: The 2022 Perseid meteor shower should produce the most meteors in the predawn hours of August 11, 12 and 13, but many faint meteors will be outshone by an almost full moon. Here’s how to get the most from this year’s shower.
*Predicted peak times and dates for 2022 meteor showers are from the American Meteor Society. Note that meteor shower peak times can vary.