M47 was discovered by Giovanni Batista Hodierna before 1654 and catalogued by Charles Messier in 1771. M47 is an open cluster, meaning that it contains young stars with the same age, composition, and distance. It is estimated to be 78 million years old at a distance of about 1,600 light-years. M47 has only 50 or so stars confirmed to be a part of the cluster.
Image: Andrea Tamanti
(I apologise for not providing my usual two images…)
Commonly called “the Seven Sisters”, M45 is one of the most well-known night-sky objects ever. Located in the constellation Taurus, M45 has deep historical roots reaching back to early human times. As it is an open cluster, it is a fairly young cluster with same chemical composition, age, and distance. Although it was catalogued by Charles Messier in 1771, it was first telescopically observed by Galileo Galilei in 1610. If you’re looking to see M45, check your local night sky closer to the spring!