CCD image taken with an STL-1301E CCD camera thru a 20-inch F/8.1 telescope focal-reduced to about F/5. The field of view is about 20x21 arc minutes, with North at the top. Total Exposure Time (LRGB) = 60 minutes.
NGC 5466 is a Globular Star Cluster in the Constellation of Boötes. It was discovered by William Herschel on May 17, 1784. It makes a fine object for small telescope observation because it is relatively large and bright.
Distance estimates for this cluster range from 51,800 Light Years (recent) to 66,850 Light Years (made in 1961). This globular cluster is unusual insofar as it contains blue "horizontal branch" stars, as well as being unusually metal poor compared to many other globular clusters. It is thought to be the source of a stellar stream discovered in 2006, called the 45 Degree Tidal Stream. This star stream is an approximately 1.4° wide star lane extending from Boötes to Ursa Major.
There are two far more distant background galaxies in the Kopernik image. The Spiral Galaxy to the right of the cluster is MCG 5-33-43, a 15.7 magnitude system at roughly 39 million light years distance.
Cluster, large, very rich in stars, very much compressed, stars of magnitude 11 and fainter.
for the latest
Globular Star Cluster Ages!!
George Normandin, KAS
September 19th, 2011