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The famous Halley’s comet is about halfway through its roughly 76-year orbit of the sun, having reached its farthest point from its host star in December 2023. The comet won’t be visible in the night sky until 2061.
But the debris the comet leaves in its trail — otherwise known as the Orionid meteor shower — causes meteors to streak through Earth’s atmosphere.
The annual celestial display will be most visible during its peak Sunday night into Monday, with an estimated rate of 10 to 20 meteors per hour, according to the American Meteor Society.
The best time to see the Orionids will be any time after midnight when constellation Orion — which is the Orionids’ radiant, or the area from which meteors appear to originate — is high in the sky, said Robert Lunsford, the fireball report coordinator for the American Meteor Society. The display will be visible in all parts of the world except Antarctica, where the sun currently does not set, he added.
But even a few days following peak activity, the Orionids are still expected to produce a similar rate of meteors. “The Orionids have a kind of a flat peak — a plateau of activity,” Lunsford said. “So, if it’s cloudy on that particular (peak) night, the night after it should be very close to the same activity you would see before.”
And later in October, the supermoon known as hunter’s moon will interfere less with meteor viewing. Appearing large and bright, this moon reached its full phase on Thursday and will continue to wane until the end of the month. Try observing meteors in the opposite direction from the moon to avoid its reflected light that could hinder visibility of faint particles, Lunsford suggested. The Orionids are active until November 22.
Meteors from Halley’s comet
As Earth orbits the sun, it encounters the debris trail from Halley’s comet twice a year. The first occurs in May when particles from the comet’s outbound leg cause the annual Eta Aquariids. The second trail, produced during Halley’s return to the sun from the outer solar system, creates the Orionids in October.
When the particles enter Earth’s atmosphere, they burn up and create the meteors we see streaking in the sky. The bigger particles can produce what are known as fireballs, meteors that are brighter than the planet Venus, according to NASA.
The particles from asteroids, which are made up of rock and metal, sometimes make it to the ground, where they are known as meteorites, Lunsford said. But a comet composed of ice, frozen gases and rocks is typically too fragile to survive a trip through Earth’s atmosphere, he added.
For sky-gazers looking to spot a meteor, NASA recommends sitting outside up to 30 minutes beforehand to let your eyes adjust to the dark. And if you’re able do your viewing at higher altitudes, the clearer the sky will be and the less moonlight will scatter, he said.
The best part of viewing a meteor shower, Lunsford said, is “getting in touch with nature and being part of the universe. Everything up there is in motion. So no one night is the same — everything has moved a little bit — and no year is the same.”
Upcoming celestial events
If you missed Comet C/2023 A3 Tsuchinshan-ATLAS and its closest pass of Earth on October 12, you still have a chance to see the comet until early November, NASA predicts. Look for the celestial wonder in the western part of the night sky shortly after sunset.
Astronomers originally estimated the comet to circle back in about 80,000 years, but as of October 14, observational data revealed the comet had a new path that could remove it from our solar system completely.
There are two full moons remaining for 2024 — the beaver moon, which is also a supermoon, on November 15 and the cold moon on December 15, according to the Farmers’ Almanac.
Meanwhile, sky-gazers can anticipate a busy meteor shower season to close out 2024. Here are peak dates for upcoming celestial activity, according to the American Meteor Society:
Southern Taurids: November 4-5
Northern Taurids: November 11-12
Leonids: November 17-18
Geminids: December 13-14
Ursids: December 21-22