Image information:

Date: 07/14/2007
Equipment: SBIG ST2000XM with CFW8a and Astronomik type 2c LRGB filter set through WO ZS105ED telescope on Losmandy GM8 mount. WO ZS105ED working at f5.6 with WO 0.8X reducer/flattener.
Image type: LRGB
Exposure time: 6X4min Luminance binned 1X1, RG&B 4X3min each binned 2X2.
Comment: M4 was low on the horizon (below 17 degrees), color data were affected

Object information:

Object designations:

M4, NGC6121
Object type:
Globular cluster
Object size:
Constellation: Scorpius
M4 in constellation of Scorpius is the closest to us globular cluster. It would be one of the most spectacular objects on our sky, if it weren't obscured by heavy clouds of dark interstellar matter in the galactic plane. That both dims and reddens its light. It is one of the loosest globular clusters and it has a remarkable feature in the form of a central bar of stars. Although containing hundreds of thousands of stars within diameter of 75 ly, M4 is one of the smallest and sparsest globular clusters known. M4 distance is 7200 ly.

Related images:

List of related images:

M4, OSC, Altair Hypercam 533C through APM/LZOS 105/650 APO telescope