Halley’s Comet debris streaks the sky on October 21, but only after the Moon sets

Halley’s Comet last swung past the Sun in 1986, yet a trail of its crumbs is still scraping across the atmosphere at 41 miles per second every October. In 2026 the Orionid meteor shower peaks on the nights of October 21 and 22, and a bright Moon is set to drown out the fainter streaks for the first half of the night.

NASA’s October skywatching guide gives the workaround in a single sentence, and it comes down to patience: skip the evening and wait for the Moon to leave the sky.

Halley’s debris and the Orion radiant

The Orionids, NASA’s guide explains, are created by tiny pieces of debris left behind by Halley’s Comet and appear to radiate from the direction of Orion. NASA’s Orionids reference page adds that the comet takes about 76 years to orbit the Sun, that its next return is expected in 2061, and that the radiant sits just north of Betelgeuse, Orion’s bright shoulder star.

Those crumbs are small, and each one burns up high in the atmosphere in a flash that lasts a fraction of a second. The streak seen from the ground is the glowing air around the grain, not the grain itself, which is why even a tiny particle at 66 kilometers per second produces a trail visible to the naked eye.

Halley feeds two showers a year because Earth crosses its orbit twice. EarthSky points out that the same comet produces the Eta Aquariids in May and the Orionids in October, the latter when Earth intercepts the debris path in late October.

A waxing gibbous Moon in the way

The Moon is the complication this year. NASA’s guide warns that a bright waxing gibbous Moon will wash out some of the fainter meteors, and Farmers’ Almanac describes it as about 80 percent lit on the peak nights. Meteors that would normally register as faint pencil lines simply vanish into the glow, which cuts the visible count even when the shower is at full strength.

The timing is what rescues the shower. A waxing Moon sets before the sky brightens, and Farmers’ Almanac puts moonset around 3 a.m. local time on the peak mornings, though the exact hour shifts with location, so a local almanac or planetarium app should be checked. EarthSky likewise says the Moon will set a few hours before dawn on the peak mornings and predicts the maximum near 18 UTC on October 21, a broad, plateau-like peak lasting several nights.

The pre-dawn window and what to expect

The date in play deserves a note, because the sources do not agree to the hour. NASA’s guide gives the peak as October 21-22 without singling out a night, while EarthSky’s prediction of 18 UTC on October 21 falls in the daytime for the Americas, which makes the pre-dawn hours of October 22 the first dark window after it for North American observers and the hours before dawn on October 21 the last one before it. Either morning is worth the early alarm, since the maximum is broad and the Moon sets on both.

NASA’s recommendation is direct: the best chance may come in just a few hours before dawn, after the Moon sets. By then the radiant in Orion has climbed well above the horizon, and the sky has had hours to darken without the Moon’s help. Star Walk’s viewing guide says much the same, advising observers to wait for the pre-dawn hours when the radiant climbs and the Moon sinks below the horizon.

Counts will be modest. NASA’s Orionids page says that under ideal dark skies observers can expect about 10 to 20 meteors per hour, while Farmers’ Almanac quotes 15 to 25 and Star Walk about 20, a spread that reflects different assumptions about sky quality. Moonlight and suburban glow push real counts lower. EarthSky tells readers to be delighted with anything above its stated 10 to 20.

The advice from all of them is to avoid staring at the radiant. NASA suggests looking 45 to 90 degrees away from Orion, where meteors trace longer trails, and lying back with feet toward the southeast in the Northern Hemisphere. No telescope or binoculars are needed, and Farmers’ Almanac notes that their narrow field of view works against meteor watching.

Because the Orionids are among the fastest annual meteors, many leave glowing trains that persist for seconds. The shower stays active from October 2 to November 7, according to Star Walk, so a cloudy October 21 does not close the window, and nights on either side of the peak still produce some meteors. NASA’s guide lists the next sky event after the shower: the Moon passing close to the Pleiades on October 27 and 28.

Halley’s own schedule supplies the one fixed number. The comet’s next return is expected in 2061, so the debris that streaks overhead this month is the nearest thing to its visit that most of today’s observers will see.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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