Messier 67

Observation Notes:

M67 is a nice, subtle open cluster, particularly in comparison to M41 which I viewed earlier in the evening. There is one bright yellow-orange star on the east side of the cluster. There are a few more orange stars scattered around. The main body of the cluster appears to be around 18′ across. The stars seem to keep to an irregular, roundish boundary. I plotted 40 stars in that area, down to mag. 11.7.


M67 resides 2,700 light years distant, and is a peculiar open cluster due to its age. Its age is estimated between 3.2 and 4 billion years, and only a few are known to be older. Open clusters usually fly apart much sooner than this. It’s anticipated that M67 can continue to exist as an open cluster for another 5 billion years. This cluster contains at least 500 stars, of which nearly 200 are white dwarfs. Because M67 is of a similar age to the solar system, and its stars have a similar composition to the sun, it is a good target for observation of solar-type stars.

Reportedly, M67 was originally discovered by Johann Elert Bode prior to 1779. Charles Messier rediscovered the cluster in 1780 and resolved it into stars.

Subject Messier 67 (NGC 2682)
Classification Open Cluster
Position Cancer [RA: 8:50.4 / Dec: +11:49]*
Size* 30′
Brightness* 6.1
Date/Time 01/16/05 – 1:30 AM
Observing Loc. Flagstaff, AZ – Home
Instrument Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag. 32 mm (37X)
Conditions Mostly clear, cold (18°F), some thin high cirrus

Seeing 5/10
Transparency Mag 5.2

*Based on published data.