M14 is an eighth magnitude globular cluster located in the constellation Ophiuchus. It was discovery by Charles Messier on June 1, 1764, who described it as a "round nebula without stars". In 1783, William Herschel became the first person to resolve it into stars. At 30,300 light-years from Earth this is one of the more distant Messier globulars. However, since it's intrinsically bright the globular can be seen with binoculars, although at best appearing only as a faint out of focus "fuzzy star".
M14 is located in a rather barren area of sky and therefore not easy to find. The cluster is positioned 8 degrees south and a little west of giant orange star Cebalrai (β Oph - mag. +2.8). Eleven degrees west of M14 are brighter globulars M10 and M12.
The best time of the year to observe it is during the months of May, June and July.
Although M14 resembles a fainter dimmer version of M10 and M12, it's still quite impressive. Through a small 80mm (3.1-inch) telescope the cluster has a bright centre surrounded by a fuzzy outer halo. A larger 200mm (8-inch) scope displays the elliptical nature of the object with some graininess, although no stars are resolvable. A telescope of 300mm (12 inches) aperture begins to resolve some of the individual stars, the brightest of which are at magnitude +14. The faint globular cluster NGC 6366 lies just over 3 degrees southwest of M14.
With an apparent mag. of +7.9, M14 is more than half a magnitude fainter than M12 and over a magnitude fainter than M10. The reason is due to distance; M14 is approx. twice as far away as M10 and M12. In reality, M14 is actually the largest of these three globulars but the distance factor wins out.
In total, M14 contains about 150,000 stars and has a spatial diameter of 100 light-years. It contains at least 70 variable stars, many of which are of the W Virginis variety. In 1938, a nova that peaked at mag. +9.2 erupted in the cluster.
M14 Data Table
|Object Type||Globular cluster|
|RA (J2000)||17h 37m 36s|
|DEC (J2000)||-03d 14m 46s|
|Apparent Size (arc mins)||11 x 11|
|Age (years)||13 Billion|
|Number of Stars||150,000|