If you only look to the sky once in a blue moon, tomorrow night is the night to do so. Casual and serious skywatchers alike can catch a glimpse of a small lunar eclipse, a full "snow" moon, and the green-headed comet—all in a single night's watch.
Not as dramatic as a full lunar eclipse, tomorrow's penumbral eclipse will only be passing through the Earth's outer shadow. Still, the next penumbral lunar eclipse won't be until 2020, so catch the show early tomorrow evening if you can. The peak of the eclipse will be at 4:43pm in the Pacific time zone, but if you wait until sunset, you should still be able to get a show of the moon as it transitions through gradually lighter shades of gray and leaves Earth's shadow behind.
Later in the evening, the gorgeous Comet 45P, also known as the "Green Comet," will be swinging by Earth—its closest appearance in more than 30 years. It's a hard comet to see with the naked eye, so grab your binoculars and look for the comet's blue-green head around midnight. Or, you can watch a live stream of the comet's cruise by astronomy organization Slooh, which starts at 7:30pm.
And of course, in between the eclipse and the comet, look up and enjoy the full moon. Nicknamed the snow moon simply because it occurs in February, it'll be up there faithfully following you on your Friday night excursions.