Messier55 is a globular cluster located in constellation Sagittarius. This cluster is very difficult to photograph from central Europe, because there is located not far from horizon. For example Charles Messier hat troubles to locate this cluster and it took him 14 years to spot it. I made a trip to Gavdos – the southernmost place is Europe. There the cluster was significantly upper in the sky.

M55 is 17600 light-year far from the Solar system, it has approximately 100 light-year diameter and contain 100 000 stars.

Techanical details

Telescope:RC 154/1370
Aperture:154 mm
Focal length:917 mm
MountiOptron CEM25P
AutoguidingQHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM
Camera:ZWO 1600 MC @ -15C
Corrector:Astro Physics CCDT67
Filters:UV, IR cut
Exposure:37x 120s Gain 240
Date:2017-09-29