Sunday, December 12
This week is Comet C/2021 A1 (Leonard)’s time to shine! Today marks its closest approach to Earth, and also the day when observers should switch from looking for the comet in the predawn sky to searching it out in the evening sky, instead.

This evening, Leonard sits 12° above the western horizon at sunset. Half an hour later, it’s just 7° high but the sky is darker and our icy target will be easier to find. A full hour after sunset, Leonard is a mere 1° high, about 5.5° northwest of magnitude 4.6 Mu (μ) Ophiuchi. 

The best comet viewing for the rest of the month will be in the evening sky, as Leonard pulls away from Earth but approaches the Sun and slowly fades to around magnitude 8. Keep watching this stunning comet throughout the week; we’ll check back in on Friday, when it will appear close to Venus in the sky.

If you aren’t able to catch the comet for yourself, consider clicking over to astronomy livestreamer David Brewer’s YouTube channel, where he’s been streaming the comet daily (weather permitting) from Denver, Colorado.

 The Geminids

The Perseid Meteor Show is better known since it happens in midsummer, but if you really want to watch a good show, bundle up in warm clothes, and observe the Geminids, the best of the meteor showers. This year there is a moon washing out the fainter ones, but night owls will get see a great show when it sets around 3 AM.

Tuesday, December 14
Let’s head back to Gemini again today, as the annual Geminid meteor shower peaks this morning with a waxing Moon in Pisces. That means bright moonlight will wash out the sky until about 3 A.M. local time (when the Moon sets), so that’s when you’ll want to step outside to scan for shooting stars until dawn.

Around 4 A.M. local time, the radiant is some 65° high in the west. It’s located just northwest of the bright star Castor. The best strategy to catch shower meteors is actually a to look a bit away from the radiant. That’s because meteors originate at the radiant, so their trails will streak away from this point. The Geminids are expected to produce up to 150 meteors per hour at their peak, so you should expect to see several shooting stars the longer you stay outside, with numbers diminishing as dawn approaches and lightens the sky. If possible, pick an observing site well away from any light pollution, bundle up (for those in colder climates), and avoid using a telescope, as its small field of view will limit or eliminate any streaks you might see. Instead, scan the sky with your eyes or binoculars to catch the most meteors.