Orionid meteor shower: where and when to watch

The Orionids have been active since the start of October, and while the peak passed in the early hours of this morning, there is still plenty to see if you are willing to wait for a clear night. The shower runs right through to 7 November, so the window is far from closed.

For context, the peak fell on the night of 21 October, between midnight and dawn, when the rate climbed to somewhere around 10 to 20 meteors per hour, with the Royal Observatory Greenwich estimating about 15. The meteors seem to radiate from the constellation Orion, near the red star Betelgeuse, and they are actually fragments of Comet 1P/Halley, which orbits the Sun every 75 to 76 years and last visited Earth in 1986. They hit our atmosphere at roughly 41 miles per second, which is why they leave such distinct streaks.

If you are planning to head out this week, there are two things worth knowing. First, the Moon has been in a waxing gibbous phase, which washes out the fainter meteors, though conditions improve once it sets below the horizon. Second, the weather is the real deciding factor: Met Éireann has issued a Status Yellow rain warning for Northern Ireland from 7pm tonight until 8am on Friday morning as Storm Austen moves in, so tonight is unlikely to be the night. If the sky stays cloudy through the morning, the shower is still there to catch on a calmer night later in the week.

When you do go, the best strategy is simple. Get away from the city lights — a dark stretch of coast or a hill in the countryside works best — and look slightly beyond the radiant in Orion rather than staring straight at it. You do not need a telescope or binoculars; the best way to see them is with the naked eye. The only real trick is patience: your eyes need about 15 to 20 minutes to fully adjust to the dark before the fainter streaks start to show up.

The Orionids are one of the most reliable showers on the calendar and can be seen from almost anywhere on Earth, so they are worth keeping an eye on whenever the clouds break. They are also the second shower linked to Halley's Comet, the other being the Eta Aquariids in May.

If you enjoy this sort of thing, the rest of the year is well supplied. The Leonids run from 6 to 30 November, peaking around 17 November with about 15 meteors an hour, and the Geminids follow in December, peaking on the 14th with a far busier rate of up to 150 per hour. The Ursids also peak around 21 to 22 December, and the Quadrantids open the new year in early January. The Perseids in the summer are the biggest of the lot, but the Orionids are a dependable autumn fixture, and with the shower active until 7 November, there is plenty of time to find a clear night and a dark spot.