Messier Number: M4
NGC Number: NGC 6121
Object Type: Globular Cluster
Distance in Light Years: 7,000
Constellation: Scorpio
Apparent Magnitude: 5.6
M4 can be easily found at 1.3º west of the bright star Antares, magnitude 1 in Scorpio. Through binoculars M4 appears as a round diffuse patch. A 4-inch telescope resolves the brightest stars of about magnitude 10.8 with an irregular distribution whilst larger telescopes show a halo of stars around the bright central portion of the cluster.
The Hubble telescope has identified at least one planet orbiting a white dwarf star in M4. These stars are among the oldest in the Milky Way, estimated at about 13 billion years old almost three times the age of our Solar System.
