French astronomer Charles Messier independently rediscovered M37 in September 1764 but all three of these clusters were recorded by Hodierna.

[citation needed] M37 exists in the antipodal direction, opposite from the Galactic Center as seen from Earth, so is in one of the nearby outer arms.

M37 has at least a dozen red giants and its hottest surviving main sequence star is of stellar classification B9 V. The abundance of elements other than hydrogen and helium, what astronomers term metallicity, is similar to, if not slightly higher than, the abundance in the Sun.

[5] At its estimated distance of around 4,500 light-years (1,400 parsecs)[1] from Earth, the cluster's angular diameter of 24 arcminutes corresponds to a physical extent of about 20–25 ly (6.1–7.7 pc).

The tidal radius of the cluster, where external gravitational perturbations begin to have a significant influence on the orbits of its member stars, is about 46–59 ly (14–18 pc).