This is the Dudley Observatory Skywatch Line for Wednesday, February 27th, and Thursday, February 28th, written by Louis Suarato.
Jupiter leads the procession of Moon and three planets overnight into Thursday morning. The 39% illuminated, waning crescent Moon, sets at 11:34 a.m. Wednesday. It rises again at 2:50 a.m. in the constellation Sagittarius. Jupiter proceeds Thursday’s moonrise by 36 minutes, and leads the crescent Moon across the overnight sky. Saturn rises at 4:02 a.m., followed by Venus 36 minutes later. Mercury rounds out your opportunity to see all the easily visible planets before it sets at 6:45 p.m. Thursday. Mercury reaches its greatest eastern elongation Wednesday. This is when Mercury’s angular separation from the Sun is at its greatest, between 18 and 28 degrees.
If you look over the western horizon after sunset, you’ll notice a very bright star almost directly overhead. That star is Capella, the brightest in the constellation Auriga, and the sixth brightest in the night sky. Auriga is also the home to three Messier objects that can easily be seen with binoculars. The three objects are opposite Capella, and form an arch swooping downward. At the top is M37, also known as the Salt and Pepper Cluster. This star cluster was discovered by Italian astronomer Giovanny Battista Hodierna before 1654. It was later discovered by Messier independently in September of 1764. M37 is the brightest of the three star clusters, and contains more than 500 stars, with 150 greater that 12th magnitude, The stars are estimated to be 4,500 light-years away, and 347 to 500 million years old. The next star cluster is M36, the Pinwheel Cluster. This star cluster, also discovered by Hodierna and Messier, is about 4,340 light-years from Earth. The Pinwheel Cluster contains at least 60 stars, with 10 stars brighter than 10th magnitude. The last star cluster in Auriga is M38, also know as NGC 1912. The brightest stars in this cluster form the Greek letter Pi. M38 contains about 100 stars, with an estimated age of 220 million years.