Giovanni Hodierna discovered M37 = NGC 2099 = h369 in 1654. Charles Messier independently discovered the cluster on 2 Sept 1764 and reported a "cluster of small stars, not far from the preceding [M36], on the parallel of Chi Aurigae; the stars are very small, very crowded and containing nebulosity; it is difficult to see the stars with an ordinary telescope of 3 feet and a half." On 4 Nov 1782, William Herschel recorded "Is an astonishing number of small stars with 227; they are almost all of the 2nd or 3rd class. I see no kind of nebulosity in the spot. With 460 the whole is resolvable into stars without nebulosity."

200/250mm - 8" very large, very rich cluster, over 150 stars, rich in mag 10-13 stars. A reddish star, HD 39183, is near the center. Best of the three bright Messier open clusters in Auriga and one of the top open clusters in the sky.

Notes by Steve Gottlieb