Messier 107

107 final

Object:   M107 (NGC 6171) Date:               2018 September 3
Type:  Globular cluster
Constellation:           Ophiuchus Time & altitude:          20.15 UT    17º
Catalogue data: Seeing (5 high):                               3/5
            R.A:                16h 32m Transparency (5 high):                   2/5
            Dec:                -13º 03 Telescope:     0.5m f4.1  Dob.
            Magnitude     8.1 Eyepiece       17mm Ethos              x120
            Size (mins)    10 Filters:            None


As on August 31, transparency overhead is good with NELM better than 5.5m and Milky Way on view but the sky gets progressively milkier below about 30 degrees. Jet contrails are another problem this evening. I can see the straight line of Mars, Saturn, Eta Oph and Zeta Oph. With the unaided eye I can see only two stars below that line, Sigma and Zeta Sgr, and Zeta is 50/50. A 3:4:5 triangle of 7th mag stars just S of M107 aids in locating it. The cluster I can see is just a haze 4 arcmins in diameter, so just the central region.