Messier 14

Messier 14
Messier 14, from 2MASS
Observation data (J2000 epoch)
Class	VIII
Constellation	Ophiuchus
Right ascension	17h 37m 36.15s[1]
Declination	-03° 14′ 45.3″[1]
Distance	30.3 kly (9.3 kpc)
Apparent magnitude (V)	+8.32[1]
Apparent dimensions (V)	11.0′
Physical characteristics
Radius	50 ly[2]
Other designations	NGC 6402[1]
See also: Globular cluster, List of globular clusters

Messier 14 (also known as M14 or NGC 6402) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier in 1764.

At a distance of about 30,000 light-years, M14 contains several hundreds of thousands of stars. At an apparent magnitude +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.

A respectable total of 70 variable stars is 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.

Messier 14 with amateur telescope

References

1. ^ ^{a b c d} "SIMBAD Astronomical Database". Results for NGC 6402. http://simbad.u-strasbg.fr/Simbad. Retrieved 2006-11-15. 
2. ^ distance × sin( diameter_angle / 2 ) = 50 ly radius

External links

• SEDS Messier pages on M14
• M14, Galactic Globular Clusters Database page
• Messier 14 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

Coordinates: 17^h 37^m 36.15^s, −03° 14′ 45.3″