Credits: Keith Turnecliff, Long Itchington
Messier 46 is a relatively bright, large cluster containing about 500 stars.
It occupies an area of 27 arc minutes of apparent sky, almost the size of the full Moon, and has a spatial diameter of 30 light years.
The cluster’s estimated age is 300 million years. M46 is moving away from us at 41.4 km/s.
The cluster has an apparent magnitude of 6.1 and lies at an approximate distance of 5,400 light years from Earth. It has the designation NGC 2437 in the New General Catalogue.
Facts about M46 by Keith Turnecliff
Messier 46 is easy to see in binoculars and small telescopes. It can be found using Sirius, the brightest star in the night sky, as it lies roughly in the same area. M46 is located 14 degrees east and 2 degrees north of the Dog Star. In 10×50 binoculars, the cluster appears hazy and almost like a nebula, but larger binoculars reveal a large open cluster with about 50 dim stars. Larger telescopes show a field of faint stars that are very similar in brightness.