Messier 20

20 final

Object:   M20  (NGC 6514) Date:               2018 August 1
Type:  Galactic nebula
Constellation:           Sagittarius Time & altitude:        22.10 UT      15º
Catalogue data: Seeing (5 high):                               2/5
            R.A:                18h 05m Transparency (5 high):                   2/5
            Dec:                -22º 30 Telescope:     0.5m f4.1  Dob.
            Magnitude     9

Eyepiece       17mm Ethos              x120

8mm Ethos              x260

            Size (mins)    17 x 12 Filters:            None


Observed an hour after culmination but low altitude even so. Many aircraft contrails are making the sky milky and there’s a lot of turbulence after another sunny day. Now the 3rd‑quarter Moon has risen the extent of the contrails is revealed!

The nebulosity is very low surface brightness and in these conditions detecting even the main features is difficult. Three dark lanes converge on an unequal pair of stars from the NE, W and S. The straight NE lane is the longest and best defined and is flanked by lines of stars. The W lane is short and curves to the N. The bright nebulosity to the N is the easiest to see while that to the SW is the hardest to detect.