- The Perseids, which NASA says is the best meteor shower of the year, happens every summer.
- The shower started in late July, but meteor activity will peak on Wednesday and Thursday.
- The Perseids are known for epic “fireball” meteors. Here are the best ways to see them.
- See more stories on Insider’s business page.
NASA calls the annual Perseids meteor shower the best of the year, thanks to the many bright meteors that streak across the night sky.
The 2021 Perseids shower peaks on Wednesday and Thursday. According to NASA, people could see up to 100 meteors an hour those nights, as Earth plows through a cloud of cometary debris. The meteors are known for their epic “fireballs” – explosions of light and color that last longer than those from typical meteors – and their long trails.
Here’s how to see the Perseids.
No need for binoculars or telescopes
The Perseids are especially visible in the Northern Hemisphere but can be glimpsed across the globe. To maximize your chance of seeing them, find a dark spot with a clear view of a cloudless, open sky. The area should be as far away from light sources as possible. (If you’re in a city, you still might spot a few meteors every hour, NASA said.)
You can see the shower starting at about 9 p.m. local time. That’s just after twilight, when you can expect long-tailed meteors lower in the sky. The best time to see the show, however, is at about 2 a.m., since more meteors are visible in the predawn hours.
You can spot the Perseids with your naked eye – in fact, NASA recommends against using telescopes or binoculars, since these instruments show only a small part of the sky at a time and meteors can come from any direction.
It helps to set aside half an hour or so to let your eyes adjust to the dark. Avoid looking at your phone, because the bright light from the screen can mess with your ability to see fainter meteors.
The Perseids meteor shower peaks around mid-August every year, but last year the moon was in its last quarter phase and rose just before the peak of the shower, so its brightness reduced the number of visible meteors.
This year, however, the crescent moon will be only about 13% illuminated by the sun on Wednesday and Thursday. That should make it easier to see more meteors during the shower’s peak. It’s worth making an effort to watch next week, because the meteor shower’s peak in 2022 will coincide with a bright full moon.
Where the Perseids come from
The annual shower gets its name from the constellation Perseus, which is where the meteors appear to originate in the sky.
But Perseus isn’t really the source of the celestial light show. The Perseids happen when Earth’s orbit takes it through a lane of space debris left behind by the comet Swift-Tuttle. Bits of rocky debris the size of sand grains and peas slam into our atmosphere at 37 miles (60km) per second, or about 133,000 mph (214,043km/h). As they burn up, they leave fiery streaks across the night sky.
It takes more than a month for Earth to pass through Swift-Tuttle’s wake, which is why the Perseids last so long.
The meteor shower’s peak comes when our planet moves through the densest part of the comet’s debris trail.