Tonight, watch for Orion the Hunter – perhaps the easiest to identify of all constellations – rising at mid-evening. It’s around late November and early December that people begin to notice Orion in the evening sky, and to comment on it. Orion will climb over your eastern horizon by around 9 p.m. tonight. You can find this constellation and watch it for months to come.
The most noticeable part of Orion is the pattern called Orion’s Belt: three medium-bright stars in a short, straight row. As seen from mid-northern latitudes, Orion appears to be lying on his side – with his Belt stars pointing upward – when he first ascends into our eastern sky in mid-evening at this time of year. Orion’s two brightest stars – Betelgeuse and Rigel – shine on opposite sides of the Belt.
As night passes, and Earth spins beneath the sky, Orion will climb higher in our sky. When this constellation is highest in the south, it is a huge, noticeable star pattern. But Orion doesn’t reach its highest point until an hour or two after midnight (that’s local time, for all times zones around the world) at this time of year.
Like all the stars, Orion’s stars rise some four minutes earlier with each passing day, or about two hours earlier with each passing month. If you see Orion shining in the east at 9:00 p.m. tonight, look for Orion to be in the same place in the sky at about 7:00 p.m. a month from now. Or if Orion is due south at 1:30 a.m. tomorrow, look for Orion to be due south at 11:30 p.m. in late December.
This shift in Orion’s location is due to Earth’s movement in orbit around the sun. As we move around the sun, our perspective on the stars surrounding us shifts. At the same hour daily, all the stars in the eastern half of the sky climb up a bit higher, whereas all the stars in the western half of the sky sink a bit closer to the western horizon.
Are you familiar with the W- or M-shaped constellation Cassiopeia the Queen? Or Polaris, the North Star? As Orion rises in the east this evening, look for Cassiopeia to soar to her highest point for the night, above Polaris in the northern sky.
Bottom line: By late November, the famous constellation Orion the Hunter is back in the evening sky! Its most recognizable feature is a short, straight line of three medium-bright stars.