M4 (NGC 6121)
Constellation: Sco
Object Type: Globular Cluster
RA: 16h 23m 35s
Dec: -26° 31' 28"
Magnitude: 5.6
Recommended minimum aperture: 50mm
Charts for 100mm Binocular (2.5° aperture circle). Click on a chart to print it.
Location:
M4 must be one of the easiest globular clusters to find. Just place Antares (α Sco) on the E of the field of view and M4 will lie at the centre.
What You Should See:
M4 is very easy to identify in any binoculars. It is relatively close to us (7 000 light years) for a globular cluster; closer than some open clusters. Owing to this closeness to us, it appears as a rather loose cluster and is one of few in which some detail is apparent in a 37×100 binocular. It would be even more spectacular were it not for intervening dust. It is in a beautifully rich star-field that is more pleasing in binoculars than in a telescope. It is the one of the largest globular clusters that is visible from the latitude of Britain, but is so low on the horizon that it is less easy to observe than M13, which is only very slightly larger.
