This image was a 3 minute exposure taken
with an ST-9E CCD camera thru Kopernik's 20-inch F/8.1 telescope. The field
of view is about 8x8 arc minutes.
There are two images below taken with the same telescope but different cameras.
This image was a 3 minute exposure taken
with an ST-9E CCD camera thru Kopernik's 20-inch F/8.1 telescope. The field
of view is about 8x8 arc minutes.
This image was a 15 minute exposure
taken with a Starlight Xpress MX-716 CCD camera thru Kopernik's 20-inch
F/8.1 telescope working at F/5.1. The field of view is about 8x6 arc minutes.
J. E. Bode (Dec. 27th, 1777): ''More or less round, with a pale glow."
W. Hershel (1783): ''A brilliant cluster, 7'-8' in diameter.'
Smyth: ''A globular cluster of minute stars; large, bright and resolvable with a very luminous center and, under the best vision, has irregular, streamy edges'
Burnham's Celestial Handbook: "The view in large instruments is stunning beyond words; the countless star images run together into a dazzling central blaze which is equaled by only a few of the globulars."
One distance estimate for M-92 is 35 thousand light years. (But Click here for the latest news on Globular Star Cluster distances and ages!!)
Globular star cluster M-92 was discovered by J.E.Bode in December 1777; Messier's independent discovery occurred in March 1781. However, it was W. Hershel in 1783 who first realized that it was a star cluster. This is a beautiful rich globular cluster which in almost any other constellation would be considered a major show object; in Hercules it has been somewhat over shadowed by the splendor of the fabulous M-13. M-92 is rather easily observed in binoculars as a fuzzy star-like object, and rather small telescopes permit some resolution of the outer edges.
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George Normandin, KAS
October 16th, 2003