Messier 36 (NGC 1960): A Pinwheel of Stars

Messier 36, nicknamed the Pinwheel Cluster, is an open cluster in the constellation of Auriga. It is best viewed in winter through early spring.

M36 is one of three impressive star clusters in Auriga (M36, M37, M38). M36 is near the same physical size as the famous Pleiades cluster, but it’s smaller in the night sky because it’s ten times away from us. Approximately 60 stars make up the cluster, with many of the brightest stars making straggling lines or chains streaming from the center.

My Observations

January 23, 2023, at 7:43 P.M.: On this night, most of the sky is clear, but a diagonal wave of cloud appears and then disappears, slashing in and out of Auriga and across to Taurus. I never drew this intriguing cluster back in 2020, so I turn my scope to M36. I first had the 12mm eyepiece but moved to the wider 20mm for a balanced look of M36’s irregular arms streaming out from the center. My mind jumps back to more than two years ago when I first observed this cluster. Little did I know back in November 2020 about the huge spike in COVID deaths yet to come after Christmas. My cousin Bobby died of COVID exactly two months after I first observed M36. But, today, life has gone on. Pain and time pass, but the stars stay. About three weeks ago, I had COVID for the first time, two years after Bobby. It came and went, and life went on. Maybe this is all too much to write on an astronomy blog, but these are thoughts I had drawing M36 reflecting on the coming through the pandemic.

Also observed on November 7, 2020, at midnight: The Auriga constellation is rich with beautiful star clusters. Before studying the sites in Auriga with a telescope, observers should scan the region with binoculars. Even under light-polluted skies, binoculars can pull out M36, M37, and M38. Based on my observations of the three prominent clusters tonight, I believe M36 is the brightest of them. While the individual stars are rather bright, the cluster is sparse and spread out across the eyepiece. The brighter stars make a stick figure-like image.

Key Stats

Constellation	Auriga
Best Viewing	Winter
Visual Magnitude	+6.0
Absolute Magnitude	-4.62
Distance from Earth	4,300 ly
Diameter	14 ly
Apparent Size	10 arcmin
Milky Way Location	Orion/Perseus Arm
My Viewing Grade	A

Historical Observations

September 2, 1764 observation by Charles Messier

“In the night of September 2 to 3, 1764, I have determined the position of a star cluster in Auriga, near the star Phi of that constellation. With an ordinary [non-achromatic] refractor of 3 feet & a half, one has difficulty to distinguish these small stars; but when employing a stronger instrument, one sees them very well; they don’t contain between them any nebulosity: their extension is about 9 minutes of arc. I have compared the middle of this cluster with the star Phi Aurigae, & I have determined its position.”

Sources and Notes

M36 photo: Atlas Image [or Atlas Image mosaic] obtained as part of the Two Micron All Sky Survey (2MASS), a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

Charles Messier Observations: SEDS Messier Database