M37
Salt and Pepper Cluster
Object Data
- Catalog Designation
- M37
- Type
- OpenCluster
- Constellation
- Auriga
- Magnitude
- 6.2
- Right Ascension
- 05h 52m 18.0s
- Declination
- +32° 33' 02.0"
- Distance
- 4,400 light-years
- Angular Size
- 24.
Survey Image
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About M37
Description
M37 is the richest and brightest of the three Auriga Messier clusters, about 4,500 light-years from Earth. It contains roughly 500 stars across about 25 light-years, with an age of 350-550 million years. The cluster is notable for containing at least a dozen red giant stars among its white and blue members, creating a subtle color contrast.
Observing Tips
Located about 3.5 degrees southeast of M36. The richest of the Auriga trio. Binoculars show a large, bright, granular patch. A telescope at 80-100x reveals a spectacular dense field of faint stars — often described as 'salt and pepper' due to the mix of faint white stars with brighter orange-red giants scattered throughout. One of the finest open clusters in the sky. Best observed from November through March.
History
Discovered by Giovanni Battista Hodierna before 1654 and independently found by Charles Messier in 1764. Its richness and beauty have made it one of the most observed open clusters by amateur astronomers.
Fun Facts
M37 contains about 150 white dwarf stars — the remnants of higher-mass stars that have already completed their evolution. The contrast between these dead stellar remnants, the red giants nearing the end of their lives, and the main-sequence stars still in their prime makes M37 a showcase of stellar evolution in a single object.
Community Photos (1)
Credit: Jim Mazur. License: CC BY-SA 4.0. (Wikimedia Commons)
Skybred Feb 28, 2026