Messier 15 is a globular cluster that is located in Pegasus, 35,000 light-years from Earth. It contains 100,000 stars in a space 175 light-years in diameter. It is located 4 degrees northwest of Enif (Epsilon Pegasi).

M15 is one of 157 globular clusters currently known in our Milky Way Galaxy. It is estimated to be one of the oldest at 12 billion years, containing some of the first stars to form in our galaxy. M15 also has one of the densest concentrations of stars known at its core which may also contain a massive black hole.

The yellow-red stars in the image are older red-giant stars in the cluster and the blue ones are younger hotter stars.

M15 shines at an apparent visual magnitude of 6.3 and an apparent diameter of 18 arcminutes.

M15 was discovered in 1746 by Jean-Dominique Maraldi.

Pease 1

M15 also contains planetary nebula Pease 1. Hold your mouse cursor over the image to see the location of the nebula.

Pease 1 was the first planetary nebula to be discovered inside a globular cluster. It was found by Francis Gladheim in 1928. It was originally cataloged as a star (Kuestner 648) by Friedrich Kuestner in 1921.

Since then, only 3 more planetary nebulae have been found in globular clusters.

Pease 1 is 3 arcseconds in apparent size with an apparent visual magnitude of 14.06. It is also cataloged as PK 65-27.1.

North is to the left in the above image.

Messier 15 Catalogs: M15, NGC 7078 Object Type: Globular Cluster Magnitude: 6.3v Size: 18' Constellation: Pegasus Image Field Centered At: RA: 21h 29m 58s Dec: +12° 09' 58" Pease 1 Catalogs: Pease 1, PK 65-27.1 Object Type: Planetary Nebula Magnitude: 14.06 Size: 3" Constellation: Pegasus Image Field Centered At: RA: 21h 30m 43s Dec: +12° 14' 02"