| Epoch | J2000 |
|---|---|
| Class | VIII[1] |
| Constellation | Ophiuchus |
| Ra | [2] |
| Dec | [2] |
| Dist ly | 30.3 kly[3] |
| Appmag v | 7.6[4] |
| Size v | 11.0′ |
| Mass msol | 1.04×106[3] |
| Radius ly | 50 ly[5] |
| Metal fe | –1.28[3] |
| Names | NGC 6402[2] |
Messier 14 (also known as M14 or NGC 6402) is a globular cluster of stars in the constellation Ophiuchus. It was discovered by Charles Messier in 1764.
At a distance of about 30,000 light-years, M14 contains several hundred thousand stars. At an apparent magnitude of +7.6 it can be easily observed with binoculars. Medium-sized telescopes will show some hint of the individual stars of which the brightest is of magnitude +14.
The total luminosity of M14 is in the order of 400,000 times that of the Sun corresponding to an absolute magnitude of −9.12. The shape of the cluster is decidedly elongated. M14 is about 100 light-years across.[6]
A total of 70 variable stars are known in M14, many of the W Virginis variety common in globular clusters. In 1938, a nova appeared, although this was not discovered until photographic plates from that time were studied in 1964. It is estimated that the nova reached a maximum brightness of magnitude +9.2, over five times brighter than the brightest 'normal' star in the cluster.
Slightly over 3° southwest of M14 lies the faint globular cluster NGC 6366.
See also
References
- ^ Shapley, Harlow & Sawyer, Helen B. (August 1927), "A Classification of Globular Clusters", Harvard College Observatory Bulletin. 849 (849): 11–14, Bibcode:1927BHarO.849...11S
- ^ "NGC 6402". Retrieved 2006-11-15.
- ^ Boyles, J. et al. (November 2011), "Young Radio Pulsars in Galactic Globular Clusters", The Astrophysical Journal. 742 (1): 51, arXiv:1108.4402. Bibcode:2011ApJ...742...51B. doi:10.1088/0004-637X/742/1/51. S2CID 118649860
- ^ "Messier 14". SEDS Messier Catalog. Retrieved 21 July 2024.
- ^ distance × sin( diameter_angle / 2 ) = 50 ly radius
- ^ "Messier 14 | Messier Objects". 31 March 2015. Retrieved 2020-04-14.
External links
- SEDS Messier pages on M14
- M14, Galactic Globular Clusters Database page
- – one of the two being M14