Messier 67
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| SDSS image of Messier 67 | |
| AladinLite | |
| Constellation | cancer |
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Position equinox : J2000.0 |
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| Right ascension | 08 h 51 m 18 s |
| declination | + 11 ° 48 ′ |
| Appearance
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| classification | II, 2, m (Trumpler), f (Shapley) |
| Brightness (visual) | 6.9 likes |
| Brightness (B-band) | 7.6 likes |
| Angular expansion | 30 ' |
| Number of stars | 500 |
| Brightest star | 10.0 mag |
| Physical data
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| Redshift | (108 ± 4) · 10 −6 |
| Radial velocity | (+32.3 ± 1.1) km / s |
| distance | 2700 ly (830 pc ) |
| Age | 4 billion years |
| history | |
| Discovered by | Johann Gottfried Koehler |
| Discovery time | 1779 |
| Catalog names | |
| M 67 • NGC 2682 • C 0847 + 120 • OCl 549 • Mel 94 • Cr 204 • Lund 490 • | |
Messier 67 (also known as NGC 2682 ) is a +6.9 mag bright open star cluster with an angular extension of 30 'in the constellation Cancer . With around 500 members, the star cluster is extremely rich and easy to find with binoculars.
Scientifically, Messier 67 is one of the most thoroughly studied star clusters. The reason for this lies in its unusually old age - for open star clusters - which is estimated at 3.5 to 5 billion years. According to the latest findings, it is around 4 billion years. This can be seen from the position of the so-called branch point in the color-brightness diagram : the cluster does not contain any main sequence stars of the spectral type F or hotter and the brightest stars in the cluster are all supergiants . The cluster contains nearly 200 known white dwarfs , over 100 sun-like stars, and many red giants . The metallicity of the members of the cluster also indicates an age of the stars that is comparable to that of our sun .
Much scientific research focuses on the evolution of the stars, since all members of Messier 67 were formed almost simultaneously and are the same distance from the observer on Earth. A small number of blue stragglers ( Blue straggler ) are the only exception, and their origin is not fully understood.
literature
- Jarrod R. Hurley, Onno R. Pols, Sverre J. Aarseth, Christopher A. Tout: A Complete N-body Model of the Old Open Cluster M67 , MNRAS 363 (2005) pp. 293-314.
- Xiao-Bin Zhang, Rong-Xian Zhang and Zhi-Ping Li: S1280 and S1284: Two Oscillating Blue Stragglers in the Open Cluster M67 , Chin. J. Astron. Astrophys. Vol. 5 (2005), No. 6, pp. 579-586
- Erik Fagerholm: About the star cluster Messier 67, inaugural dissertation , Uppsala 1906
Web links
- astronews.com: Three planets discovered at Messier 67 January 15, 2014
- astronews.com: More hot Jupiter in star clusters June 21, 2016
- Spektrum .de: amateur recordings [1]
