The NASA/ESA Hubble Space Telescope has presented the best-ever view of an oldest and mysterious globular cluster Messier 15, which has a huge collection of stars revolving the center of the Milky Way.
In the above image, blue points are representing hotter stars and golden color points are representing cooler stars. All of them are increasingly concentrating towards the center of the cluster. Bright blue object just to the left of the center represents planetary nebulae, Pease 1.
Messier 15 is present about 35,000 light-years away from us in the constellation Pegasus the Winged Horse. With an age of about 12 billion years and with a huge collection of over 100,000 stars, it is one of the oldest and densest globular clusters known. Astronomers are of the opinion that there is an intermediate-mass black hole at the center of the cluster. Messier 15 is the first globular cluster known to have nebulae.
Hubble views an old and mysterious cluster – Astronomy (http://www.astronomy.com/news/2013/11/hubble-views-an-old-and-mysterious-cluster)