Messier 14

Messier 14
Globular cluster Messier 14 in Ophiuchus
Observation data (J2000 epoch)
Class	VIII[1]
Constellation	Ophiuchus
Right ascension	17^h 37^m 36.15^s[2]
Declination	–03° 14′ 45.3″[2]
Distance	30.3 kly (9.3 kpc)[3]
Apparent magnitude (V)	7.6[4]
Apparent dimensions (V)	11.0′
Physical characteristics
Mass	1.04×10^6[3] M☉
Radius	50 ly[5]
Metallicity	${\displaystyle {\begin{smallmatrix}\left[{\ce {Fe}}/{\ce {H}}\right]\end{smallmatrix}}}$ = –1.28[3] dex
Other designations	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.

Gallery

• 
  Messier 14 with amateur telescope
• 
  Map showing location of Messier 14

See also

• List of Messier objects

References

1. Shapley, Harlow; Sawyer, Helen B. (August 1927), "A Classification of Globular Clusters", Harvard College Observatory Bulletin, 849 (849): 11–14, Bibcode:1927BHarO.849...11S.
2. "NGC 6402". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2006-11-15.
3. 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.
4. "Messier 14". SEDS Messier Catalog. Retrieved 21 July 2024.
5. distance × sin( diameter_angle / 2 ) = 50 ly radius
6. "Messier 14 | Messier Objects". 31 March 2015. Retrieved 2020-04-14.

External links

• SEDS Messier pages on M14
• M14, Galactic Globular Clusters Database page
• NASA Astronomy Picture of the Day: The Comet and the Star Cluster (11 April 2016) - one of the two being M14
• Messier 14 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images