The last major meteor showers of 2021 will all be affected by moonlight. The Orionid meteor shower in October peaked on the night of Full Moon, and the Leonid meteor shower this month will fare little better. The Leonid shower will peak around November 17, with a maximum zenith hourly rate (ZHR) of 10–15. Full Moon will be on the 19th, so moonlight will interfere with meteor observation nearly all night on the peak night of the Leonid shower.
The Geminid meteor shower will peak on the night of December 13–14, five days before Full Moon, so it will not be affected quite as much by moonlight. The Moon will set in the early morning hours on the peak night, leaving several hours of darkness for meteor observing before sunrise. The Geminid shower is the strongest shower of the year, with a ZHR around 150, and, unlike most meteor showers, it produces large numbers of meteors in both the evening and morning hours. Because of these factors, you should be able to see a fair number of meteors anytime on the peak night, even before moonset.
Moonlight can hamper meteor observing, but the Moon can also be the source of beautiful astronomical phenomena. On November 19, the Moon will be darkened for several hours by a partial lunar eclipse. At the peak of the eclipse, which will occur at 9:02 UTC (4:02 a.m. EST), the Moon will be almost entirely covered by Earth’s shadow.
Most or all of the eclipse will be visible from the Americas, Oceania, and eastern Asia.
The most exciting astronomical event of November and December may be Comet Leonard. Comet C/2021 A1 (Leonard) was just discovered on January 3 of this year, but it shows promise of becoming the best comet of 2021. Comet Leonard is predicted to brighten considerably throughout November and early December, and it may become faintly visible to the unaided eye during mid-December. Even if it doesn’t brighten quite that much, it should still be an easy binocular target.
Comet Leonard will be a morning object in early December as it moves southeast through the constellations of Bootes, Serpens Caput, and Ophiuchus. Around or just after its closest approach to Earth on December 12, the comet will transition to the evening sky, where it will be visible above the horizon just after dark as it moves across the constellation Sagittarius. The most predictable thing about comets is their unpredictability, but at this point, Comet Leonard is on track to be an exciting close to 2021.
In Our Skies, November 2021: Comet Leonard
