Courtesy of EarthSky
A Clear Voice for Science
www.EarthSky.org

Monoceros and Orion in the early evening

Today’s chart shows something you’ll need a very dark sky to see. In fact, the view will probably be better after the waxing crescent moon sets around mid-evening tonight. Focus in on the stars Betelgeuse, Sirius and Procyon. They make a triangle, which is sometimes called the Winter Triangle. Within this triangle of stars, hidden in between the many bright and glittering stars and constellations visible at this time of year, there’s a constellation that’s as elusive in our night sky as its namesake is in countless fairy tales.

This is the constellation Monoceros the Unicorn. We show it to you now not so much so that you can see it … indeed Monoceros is all but impossible to see in any but the darkest skies.

And yet, like all of the night sky, this region of the heavens does hold interest. The winter Milky Way runs through here, so it’s a good place to scan with binoculars. Those with dark skies might try drawing an imaginary line from the star Sirius to Procyon.

About a third of the way along this line, you’ll find a hazy object, an open star cluster, called M50. This object needs a telescope to show it clearly. But it’s wonderful to contemplate this cluster of stars on a winter night. There are really about 100 stars in the little patch we know as M50. The main part of the cluster is about 10 light-years across. The entire cluster is located some 3,000 light-years from us.

Written by Deborah Byrd