Night Sky: Should you attempt Comet Leonard?

Photos like this bear no resemblance to what you’ll see if you observe comet Leonard through your binoculars. (Astronomy Magazine)

It’s easy to get tempted by the Web headlines. They make it sound amazing: “Are you ready for the big comet show?” and “Don’t Miss 2021’s Best Comet.”

But there’s a problem: Few will see any trace of this comet. It’s far fainter than last year’s Comet Neowise, and that was a challenge for most. To be sure, there is indeed some good news. The comet’s location is easy to find, since it’s directly left of super-dazzling Venus from now through New Year’s. Also, at magnitude 5, it’s a bit brighter than forecast, so that it now technically matches the faintest star of the Little Dipper, which is visible to the naked eye.

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But it’s oh-so-low, meaning its dim light must bulldoze its way through thick horizon air, and not be blocked by any distant hills, which are abundant in our region. Moreover, a 5th magnitude star is one thing; a 5th magnitude comet is quite another, since that same brightness is spread out over a wide area, making it much harder to detect. But binoculars should do the job.

Perhaps the biggest issue is that you need inky-black conditions. Our unpolluted skies will be adequate if you’re away from city lights. So if you have binoculars and live in or can get to a place with an unblocked southwestern horizon all the way down, sweep them far left of Venus as soon as full darkness falls, around 5:30 p.m.

This observer, meaning myself, has been watching comets for more than a half century, and lives in our dark mountains, and even has an observatory, and I’m not too excited. That’s because those gorgeous photos you’ve seen showing a lovely green nucleus and coma, along with a distinct tail, are not what your binoculars will reveal if you see it in person. Viewed in real time, live, your binoculars will probably show it as a mere blurry blob with no tail and no color. So that’s what to expect, as you decide whether this is a worthwhile celestial endeavor.

But hey, it’ll be fun to try, a triumph if you succeed, and in any case you’ll be staring at Venus at its best. In fact, do also point those binoculars at that dazzling planet and, if they’re steadily braced or image stabilized, you’ll see its current moonlike crescent shape. It’s win-win. Sort of.