Messier 14 (also known as M14 or NGC 6402) is a

globular cluster A globular cluster is a spheroidal conglomeration of stars. Globular clusters are bound together by gravity, with a higher concentration of stars towards their centers. They can contain anywhere from tens of thousands to many millions of membe ...

of stars in the constellation

Ophiuchus Ophiuchus () is a large constellation straddling the celestial equator. Its name comes from the Ancient Greek (), meaning "serpent-bearer", and it is commonly represented as a man grasping a snake. The serpent is represented by the constella ...

. It was discovered by

Charles Messier Charles Messier (; 26 June 1730 – 12 April 1817) was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the ''Messier objects''. Messier's purpose ...

in 1764. At a distance of about 30,000 light-years, M14 contains several hundred thousand stars. At an

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

of +7.6 it can be easily observed with binoculars. Medium-sized

telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observ ...

s 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 The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

corresponding to an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it ...

of -9.12. The shape of the cluster is decidedly elongated. M14 is about 100 light-years across. A total of 70

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as e ...

s are known in M14, many of the

W Virginis W Virginis is the prototype W Virginis variable, a subclass of the Cepheid variable stars. It is located in the constellation Virgo (constellation), Virgo, and varies between magnitudes 9.46 and 10.75 over a period of approximately 17 day ...

variety common in globular clusters. In 1938, a nova appeared, although this was not discovered until

photographic plates Photographic plates preceded photographic film as a capture medium in photography, and were still used in some communities up until the late 20th century. The light-sensitive emulsion of silver salts was coated on a glass plate, typically thinn ...

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 NGC 6366 is a globular cluster located in the constellation Ophiuchus. It is designated as XI in the galaxy morphological classification scheme and was discovered by the German astronomer Friedrich August Theodor Winnecke on 12 April 1860. It is ...

Gallery

File:M14HunterWilson.jpg, Messier 14 with amateur telescope File:M14map.png, Map showing location of Messier 14

References

External links

SEDS Messier pages on M14

M14, Galactic Globular Clusters Database page
* - one of the two being M14 * {{Sky, 17, 37, 36.15, -, 03, 14, 45.3, 30300 Messier 014 Messier 014 014 Messier 014 17640601

Gallery

See also

References

External links