The best meteor showers of the year

A meteor shower happens when the Earth in its orbit ploughs through the dust trail left behind by a comet (or in two famous cases, an asteroid). The grains of dust hit the upper atmosphere at thirty to seventy kilometres per second, glow briefly as they vaporize, and we call them shooting stars. From any one location, on the peak night of a good shower, you can see between ten and a hundred meteors per hour, more if you’re lucky and the geometry is favorable.

There are dozens of named meteor showers in the calendar, but only about six are reliably worth getting out of bed for. The others produce so few meteors per hour that you have to be paying close attention to notice them happening.

The ones worth setting an alarm for

The Perseids peak around the 12th and 13th of August every year. They average a hundred meteors per hour at the peak under ideal conditions, and crucially, they happen in warm summer weather in the Northern Hemisphere. This combination makes them by far the most-watched shower. They radiate from the constellation Perseus, in the northeast around midnight. Their parent body is the comet Swift-Tuttle, which last passed the Sun in 1992 and won’t be back until 2126.

The Geminids peak on the 13th and 14th of December. They are technically the richest shower of the year, with peak rates around 150 per hour, and they’re known for slow, bright meteors that often have color (the dust grains are denser than average). The catch is that they happen in cold winter weather and you’ll be lying outside under a sleeping bag at three in the morning to see them properly. Their parent is unusual: an asteroid called 3200 Phaethon rather than a comet.

The Quadrantids peak in the first days of January. Rates can hit 110 per hour but the peak is brief, often just a few hours, and many years the peak happens during your daytime. They radiate from a constellation called Boötes (the original constellation Quadrans Muralis, which gave the shower its name, has since been abolished). Cold, but rewarding if your peak happens at night.

The Eta Aquariids in early May are best from the Southern Hemisphere, where the radiant rises higher. From the north they’re decent but not spectacular. They’re the leftover dust from Halley’s Comet, which also produces the October Orionids — meaning Halley contributes to two showers per year on opposite sides of Earth’s orbit.

The Orionids in late October are moderate at fifteen to twenty per hour. The Leonids in mid-November are usually quiet at about that rate too, but every thirty-three years they produce a meteor storm that goes well over a thousand per hour. The last big Leonid storm was in 1999 and 2001. The next is predicted around 2032.

A useful thing to know about timing

Meteor showers are nearly always better after midnight, and best in the hours just before dawn. The reason is straightforward physics. Before midnight, your part of the Earth is on the trailing side of our motion around the Sun, and you only see meteors that catch up to us. After midnight, your part is on the leading side, like the windshield of a car, and you see both the meteors catching up and the ones we’re running into. The difference can be a factor of two or three in the rate.

If you can only stay out for half an hour, do it between two and four AM. If you can stay out all night, the rate will climb steadily into the small hours and stay good until twilight starts.

What spoils a shower

A full moon is the biggest enemy. Bright moonlight floods the sky and you only see the brightest meteors, which means you might count ten an hour during a Perseids peak that should have been a hundred. Check the moon phase before committing to a long night out. The major showers are worth waiting a year for if the moon is going to wreck this year’s event.

Clouds are the other obvious problem, and the only solution is to be flexible about where you go. If your local forecast is clear within driving range, drive there. Many shower peaks fall on consecutive nights, so if night one is cloudy, night two often works.

Equipment

The right amount of equipment for meteor showers is none. Binoculars and telescopes actively hurt because they restrict your field of view, and meteors can appear anywhere in the sky. The most productive setup is a reclining lawn chair, a blanket, a thermos of something warm, and the patience to stare at a big patch of sky for an hour or two without distraction. The first ten minutes you might see one or two and feel disappointed. The hour after that, when your eyes are fully dark-adapted and the radiant has climbed higher, you’ll see what you came for.