Two annual meteor streams offer good cause to watch the sky in October.
Fall meteor season has begun. Late October not only sees dusk falling ever earlier as ghouls and goblins walk the Earth on Halloween, but it also sees the peak of two fine annual meteor showers kicking off Halloween season: the Orionid and Taurid meteor showers.
The Orionids always make the top of the dozen or so annual meteor showers worth watching for. The source of the Orionids is that most famous of all periodic comets, 1P/Halley. On a 75 year orbit, Halley just reached aphelion over 35 Astronomical Units from the Sun out beyond the orbit of Neptune on December 9th, 2023. Halley’s Comet is actually the source of a second annual meteor shower, the springtime Eta Aquariids. Halley’s Comet now begins its long plunge sunward towards its next perihelion apparition in 2061.
Halley's Comet, imaged from Arequipa Observatory in Peru in 1910. Credit: Public Domain.
In 2026, the Orionids are expected to top out at a Zenithal Hourly Rate (ZHR) of 20 meteors per hour. Jupiter seems to play a role in modifying the Orionid meteor stream, and we tend to see an enhanced uptick from the shower about mid-decade or so, as last occurred in 2006. The expected peak for the shower arrives around October 21st, but the shower is also active for most of the last half of October.
The orbit of Halley's Comet, plus its position in 2026. Credit: NASA/JPL
If you can trace a meteor back to the club of Orion the Hunter and its junction with Gemini the Twins, then you’ve probably caught sight of an Orionid.
The Orionid, Taurid and antihelion source radiants in the sky. Credit: Stellarium
In 2026, the Moon is waxing gibbous at the Orionids' peak, just 5 days prior to the Full Hunter’s Moon on October 26th.
A 2022 Orionid. Credit: Filipp Romanov
“October-November is my favorite time for meteor observing,” astrophotographer Eliot Herman told Universe Today. “While the Geminids can be great for one night (and) the Orionids and Taurids are not as prolific, the Orionids are scattered over days and the Taurids continue for weeks, often with bright fireballs. In addition, there are several other meteor showers occurring in the same time frame (the November Leonids and the Draconids). While none of these are major showers, together, this period brings together many opportunities to see meteors of differing colors, brightness, and sources.”
Next up, the Taurid meteor stream is active in late October into November. These are the notorious ‘Halloween Fireballs’ which often light up social media as late Fall nights draw pedestrian skywatchers out after hours. The source of the Taurids is the second periodic comet on the tally, 2P/Encke. This comet also has the distinction of having the shortest known orbit of just 3.3 years.
Clearly, there’s something intriguing about the complex debris stream from Comet Encke. While the Taurids barely top a ZHR of 5 on most years barely above the background sporadic rate, they are also a prodigious producer of fireballs. Taurids are also slow movers, approaching the Earth from behind and frequently leaving long, stately trains across the sky.
The morphology of a 2022 Taurid fireball. Credit: Frankie Lucena
2P/Encke reaches perihelion in just a few months on February 10th 2027, so we could be due for an enhanced showing from the northern and southern Taurids this year. Note that in late October, the antihelion source where many sporadics hail from is nearby along the ecliptic plane in the constellation Aries the Ram, while the Northern Taurid radiant drifts from Taurus into Aries, and the Southern Taurid point source lies nearby in Cetus the Whale.
Meteor watching requires nothing more than a set of working 'Mk-1 eyeballs' and patience. A camera with a wide-angle lens equipped with an intervalometer can automate the meteor capturing process, leaving you free to watch the sky.
It’s great to see these ghostly remnants of Halley’s and other forgotten comets of yore silently piercing the night. Be sure to watch for October meteors, and ponder the returns of two historic comets.