Similar to M6, there is another bright open cluster in constellation Scorpius called Ptolemy Cluster or Messier 7. The cluster was discovered very long time ago (130 BC) by Greek astronomer Klaudios Ptolemaios. It belongs to one of the brightest and the biggest star clusters, which are visible by naked eye, but not from Central and Northern Europe. The open cluster M7 consists of several hundreds of blue stars and it’s approximately 1000 light-year away from Solar System. The background illuminates our home galaxy Milky Way.
To capture this cluster was quite tricky. First two attempts were interrupted by windy and cloudy weather. During the third one I managed to expose 17x 120s and 8x 180s, i.e. 58 minutest in total.
|Telescope:||Newton 150/600 mm|
|Focal length:||660 mm|
|Autoguiding||QHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM|
|Camera:||ZWO 071 Pro @-10C|
|Corrector:||Explore Scientific HR coma corrector|
|Filters:||Astronomik L-1 - UV IR Block Filter|
|Exposure||17x120s, 8x180s, Gain 134, bin 1x1,|