Comet Leonard will light up the sky this month — here’s how to see it
December is Leonard’s month
Comet Leonard’s brightness should noticeably ramp up as it approaches the Earth. In the early days of December, observers who are up around the break of dawn (roughly 5:30 a.m. local time), should concentrate on the eastern sky about halfway up from the horizon to the point directly overhead. Now, with binoculars, scan that part of the sky roughly midway between the 3rd-magnitude star Cor Caroli in the constellation Canes Venatici (the Hunting Dogs) and the 3rd-magnitude star Muphrid in the extended foot of Boötes the Herdsman.
There, you should run across a circular, fuzzy, 6th-magnitude glow perhaps sporting a tail. That will be Comet Leonard.
For most of us, the second week of December is when Comet Leonard should be most interesting, offering the best compromise between increasing brightness and decreasing altitude at the start of dawn. Moreover, the sky will be free of moonlight, as it will be shortly after the new moon of Dec. 4.
On the morning of Dec. 6, about two hours before sunrise, look toward the eastern sky. You will immediately notice the brilliant orange-yellow star, Arcturus in the constellation of Boötes the Herdsman. Now, with binoculars, scan that part of the sky about 5 degrees to the left of Arcturus and you should see Comet Leonard. The comet’s dust tail, which started to lengthen noticeably during early November, should be pointing almost straight up.