"Tonight's Sky" is written by retired planetarium director Dave Leake and reprinted with his permission. See Dave Leake's Prairie Skies column in the Champaign–Urbana News-Gazette each Sunday. Dave Leake's preview of 2020 sky events can be found here.
January 5 – 11
Happy New Year, everyone! Welcome to another year of stargazing. Venus is the only easily-visible planet in our evening sky, brightening the southwest after sunset. Venus will be the brightest object in our darkened sky, save for the Moon. Watch carefully as it gets a little higher above the horizon each evening this month. Friday is the year’s first full Moon. The January full Moon has been known as the “Wolf Moon” as wolves howled near Native American encampments. There’s a slight lunar eclipse on Friday but we’re on the daytime side of the Earth during the event. At this Thursday’s CU Astronomical Society meeting (7pm, planetarium) we’ll look at noteworthy sky events this year on the dome. My annual preview is on the planetarium web site.
January 12 – 18
After 6:30pm all this week, look eastward for the belt stars of Orion the Hunter. The three stars will make a nearly-vertical line to the horizon. Trace them downward and watch the star Sirius rise. Sirius is the brightest nighttime star and an important star to the Egyptians. When Sirius rose just before the Sun, the Nile River was about to flood, signaling the beginning of their agricultural year. As you look towards the horizon, you’re looking through 40 times more air than if you were looking straight up. The thicker air distorts the starlight, making Sirius twinkle and change colors. This Friday, early risers can see the planet Mars above the red star Antares in the southeast.
January 19 – 25
The Moon is situated in the morning sky this week, making a nice triangle with Mars and the star Antares tomorrow morning. If you’re free Tuesday night, join me at the Urbana Free Library for a 7pm presentation on what we’ll see in the sky this year, including a little background info for the novice. The planetarium is open this weekend with Winter Prairie Skies, From Earth to the Universe and Amazing Stargazing for the kids, all playing. Check out the schedule online. See if you can find the Big Dipper this week. The familiar dipper is above the horizon all year, but during cold Midwestern winters, it’s lurking just above the northeastern horizon after sunset.
January 26 – February 1
Skywatchers with telescopes should check out Venus tomorrow night but wait until it appears in a darkened sky. Venus is placed just above and left of the much-more-distant Neptune. Neptune is larger than Venus but nearly 28 times farther away and thus appears pretty faint. If you don’t have a telescope, look for a beautiful crescent Moon sitting below Venus. Tuesday is equally good with the Moon to the upper left of the planet. Far to the lower right of the pair is Mercury. If you can find the “M”-shaped constellation Cassiopeia in the northwest, look for the Double Cluster in binoculars above the “M.” This week, Comet PanSTARRS will pass near the cluster but comets are notorious for changing brightness.