Discovered May 17, 1784 by William Herschel.
Located in the constellation Bootes, NGC 5466 is a very loose globular cluster with a concentration class of XII. This class is a measure of the concentration of stars within the cluster. The XII designation is the least concentrated of all cluster classes.
Several RR Lyrae stars have been observed in the cluster. These stars are variable and can be used to determine the distance to the cluster. Photometric studies of these variables have determined the cluster is approximately 52,000 (16 kpc +/- .6 kpc) light years from the Earth.
Along with blue stragglers, there is a population of blue horizontal branch stars within the cluster.
Observations of the cluster stars have yielded an estimated the age of the cluster to be 13.57 billion years.