Globular Star Cluster M-4 (NGC 6121) in Scorpius

There are two images of the cluster below. The first is a a color image covering only the inner part of the cluster taken with our 20-inch telescope. The second is a wide field black & white image taken thru our 80mm VERNONscope refractor.


Globular Cluster, M-4
A CCD image taken with an STL-1301E CCD camera thru our 20-inch F/8.1 telescope working at F/5. The field of view is about 20x20 arc minutes. This image only shows the inner portion of the cluster. M-4 was only 19 degrees above the horizon when this image was taken.


Globular Cluster, M-4
A CCD image taken with an Starlight Xpress MX-716 CCD camera thru our VERNONscope 80mm refractor working at F/6.25. The field of view is about 60 x 45 arc minutes.


P.L. de Cheseaux (Discovered M-4 in 1746):

Charles Messier (May 8th, 1764):

Quote from Burnham's Celestial Handbook:

Description of M-4 in The Deep Sky Field Guide to Uranometria 2000 (c) Willmann-Bell, Inc.:


This cluster was discovered in 1746 by de Cheseaux. Current estimates place M-4 at a distance of 10,000 light years, with an age of 14 billion years. (But Click here for the latest news on Globular Star Cluster distances and ages!!).