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.
Technical details:
Telescope: | Newton 150/600 mm |
Aperture: | 150 mm |
Focal length: | 660 mm |
Mount | iOptron CEM25P |
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, |
Date: | 2018-09-04 |
[…] capture nearly all Messier’s summer objects in southern skies. Specifically, I captured M4, M6, M7, M8, M9, M17, M18, M19, M22, M23, M24, M25, M28, M30, M31, M33, M45, M55, M56, M62, M69, M70, M73, […]
[…] observe or photograph this cluster have astronomers or astrophotographers in southern countries. My last attempt to capture it in Grease was constantly disturbed by the weather, therefore we I was again in South, […]