Orionid meteor shower: How to see debris from Halley's Comet

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The famous Halley's Comet is about halfway through its 76-year orbit around the sun and reached its furthest point from its home star in December 2023. The comet will not be visible in the night sky until 2061.

But the debris the comet leaves in its wake – also known as the Orionid meteor shower – causes meteors to streak through Earth's atmosphere.

According to the American Meteor Society, the annual sky show will be most visible during its peak Sunday night into Monday, with an estimated rate of 10 to 20 meteors per hour.

The best time to see the Orionids is any time after midnight, when the Orion constellation – the constellation of the Orionids, or the area where meteors appear to come from – is high in the sky, said Robert Lunsford, the fireball reports coordinator American Meteor Society. The display will be visible in all parts of the world except Antarctica, where the sun does not currently set, he added.

But even a few days after peak activity, the Orionids are still expected to produce a similar rate of meteorites. “The Orionids have a sort of flat top – a plateau of activity,” Lunsford said. “So if it's cloudy on that particular (peak) night, the night after that should be very similar to the activity you saw before.”

And later in October, the supermoon known as the Hunter's Moon will have less of an impact on meteor viewing. This moon appears large and bright, reaching full phase on Thursday and will continue to wane through the end of the month. Try observing meteors in the opposite direction from the moon to avoid their reflected light, which could affect the visibility of faint particles, Lunsford suggested. The Orionids are active until November 22nd.

As the Earth orbits the Sun, it encounters the debris trail of Halley's Comet twice a year. The first occurs in May, when particles from the comet's outgoing leg cause the annual Eta Aquariids. The second track, formed during Halley's return to the Sun from the outer solar system, produces the Orionids in October.

When the particles enter the Earth's atmosphere, they burn up, creating the meteors we see streaking across the sky. According to NASA, the larger particles can create so-called fireballs, meteors that are brighter than the planet Venus.

The particles from asteroids, which are made of rock and metal, sometimes end up on Earth, where they are called meteorites, Lunsford said. But a comet, made of ice, frozen gases and rock, is usually too fragile to survive a journey through Earth's atmosphere, he added.

For sky watchers looking for a meteor, NASA recommends sitting outside up to 30 minutes beforehand to allow your eyes to adjust to the darkness. And if you're able to do the observations at higher altitudes, the sky will be clearer and the moonlight will be scattered that much less, he said.

The best part of watching a meteor shower, Lunsford said, is “getting in touch with nature and being part of the universe.” Everything is moving up there. That’s why no two nights are the same – everything has changed a little – and no two years are the same.”

If you missed comet C/2023 A3 Tsuchinshan-ATLAS and its next flyby of Earth on October 12, you still have a chance to see the comet until early November, according to NASA. Just after sunset, look for the celestial wonder in the western part of the night sky.

Astronomers originally estimated that the comet would orbit again in about 80,000 years, but on October 14, observational data showed that the comet had a new orbit that could remove it from our solar system entirely.

Two full moons remain for 2024 – the Beaver Moon, which is also a supermoon, on Nov. 15 and the Cold Moon on Dec. 15, according to the Farmers' Almanac.

In the meantime, sky watchers can expect a busy meteor shower season as 2024 comes to a close. According to the American Meteor Society, here are the peak dates for upcoming celestial activity:

Southern Taurids: 4th-5th November

Northern Taurids: 11th-12th November

Leonids: 17th-18th November

Geminids: 13th-14th December

Ursids: 21st-22nd December