Messier 14

Messier 14 or M14 (also known as NGC 6402 ) is a 7.9 like bright globular clusters with a surface area of 11.0 ' in the constellation Ophiuchus ( Ophiuchus ). The brightness information from various sources will be 7.6 to 8.3 mag.

He is over 1 million solar masses, although the heaviest, but by absorbance of the faintest of 5 globular clusters of the constellation (M9, 10, 12, 14 and 107). Therefore, it is difficult to see in a 10 × 50 binoculars. Telescopes from 15 -20cm opening only show a mottled discs, while the first single stars appear only at 30 cm aperture and at least 150 - fold magnification.

M14 was discovered on June 1, 1764 by the French astronomer Charles Messier, 2 days after M10 and M12. But in 1783 it was William Herschel resolved into individual stars whose brightest is only 14 size. The distance is depending on the measurement method 28000-56000 light years. One difficulty is that the galactic dust attenuates its brightness by about 2 mag.

The cluster center acts speckled, the South East has a dark cloud, and is not completely dissolve in large telescopes; some star chains cross it diagonally. A total of 68 variables were identified, including 55 of the typical old RR Lyrae stars. 1938 appeared a nova of 16 mag, but which was discovered only in 1964 in photographs - the first time in a globular cluster.