Fall 2021 offers up an all-night parade of challenging telescopic comets.
Ready for the next big one? If you’re like us, the surprise appearance of Comet F3 NEOWISE last summer was a great teaser of what could be. To be sure, we’re still long overdue for the next great naked eye comet, but there’s always a steady stream of fainter fuzzies out there for owners of large light buckets to hunt down. Fall of 2021 sees half a dozen comets knocking on binocular visibility around +10th magnitude, from dusk ‘til dawn. So without further fanfare, here are the best cometary targets for September into October 2021:
The Sept-Oct path of Comet 8P/Tuttle. Credit: Starry Night.
Orbital period: 13.6 years.
Perihelion: August 27th, 2021.
Fun fact: 8P Tuttle is the cometary source of the December Ursid meteor shower.
An image of comet 8P/Tuttle near the galaxy M33 from its favorable 2007 apparition. Credit: Wikimedia Commons/VC Castro/Free Art License CCSA 3.0.
2021 Visibility prospects: The comet tops out +8th mag in September, but sits low to the east at dawn for northern hemisphere. The southern hemisphere gets a better view in October, as the comet plunges through the long snaking constellation of Hydra.
Key date: On September12th the comet passes two degrees from the +2 magnitude star Alphard (Alpha Hydrae).
The Sept-Oct path of Comet 4P/Faye. Credit: Starry Night.
Orbital period: 7.6 years.
Perihelion: September 8th, 2021
Fun Fact: Note its low discovery number: 4P Faye was only the 4th periodic comet discovered, after 1P Halley, 2P Encke and ‘lost’ comet 3D Biela.
2021 visibility prospects: Fresh off perihelion this week, 4P/Faye maintains good visibility for northern hemisphere observers high in the dawn in September-October, crossing Taurus into Orion and Gemini and shining at +11th to +10th magnitude.
Key Date: On October 27th, the comet passes just 40’ from the +3.3 magnitude star Alzirr (Xi Geminorum).