Messier 4

4 final

Object:   M4  (NGC 6121) Date:               2018 June 2
Type:  Globular cluster
Constellation:           Scorpio Time & altitude:         23.50 UT      12º
Catalogue data: Seeing (5 high):                               3/5
            R.A:                16h 24m Transparency (5 high):                   2/5
            Dec:                -26º 32 Telescope:     0.5m f4.1  Dob.
            Magnitude     5.9 Eyepiece       17mm Ethos              x120
            Size (mins)    26 Filters:            Lumicon deep sky


A very poor view even though it is on the S meridian. Naked eye limiting magnitude in this part of the sky is about 3.5 and in the eyepiece the sky background is glaring. The gibbous Moon, four days past full has cleared the SE horizon. Curiously, the mediocre conditions emphasis the diametrical line of stars running NS across the cluster. The rest of the cluster is barely visible. I have had more satisfying views of M4 using 18×50 IS binoculars.