Category: Asterism


I went to Crete without a detailed plan on which deep space objects to capture. The primary target was Rho Ophiuchi, which I captured really well. Then I started to think about the next objects. Obviously, if you are in a dark place, you can point your camera nearly anywhere. However, there are some regions full of stars and deep space objects. For example constellation Cygnus, which is sometimes called the Northern Cross. It is located visually on the plane of the Milky Way galactic disk, therefore there are many deep space objects.

Let’s have a look at a wide-field picture captured by a 24 mm lens attached to Canon EOS 6Da:

Let’s zoom a bit by changing the lens to a 50 mm focal length. Here the constellation is perfectly centered:

Let’s zoom further to the central star Sadr by change of the lens to 180 mm focal length:

Let’s keep the focal length 180 mm and let’s have a look at the left star Deneb and very famous North America nebula:

Again, let’s keep the focal length 180 mm and change to perspective to the bottom (eastern) star Aljanah, where the beautiful supernova remnant the Veil nebula is located:

In total, the camera collected 15.5 hours of light and I am happy with the result.

M40 Double Star

Messier 40 is a double star located in constellation Ursa Major (in the middle of the picture). Charles Messier was searching for the nebula in this part of the sky, which was observed by Johannes Hevelius. He was unable to locate any nebulous object, but he found this double star and catalogued them under the number 40. Double star should be a system of two stars, which are bonded by the gravity, but the latest measurements demonstrated that these two stars are close to each other only visually and they are completely unrelated.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1060 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure40x120s, Gain 94, bin 1x1,

M73 Asterism of four stars

Messier73 is a group of stars (asterism), which are visually close to each other if viewed from Earth. M73 was discovered by Charles Messier on October 4 1780 and catalogued as an open cluster with some nebulosity. Latest investigation revealed that M73 is not a cluster, but just an asterism.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length660 mm
MountiOptron CEM25P
AutoguidingQHYCCD miniGuideScope 130 mm f/4.3, ZWO 174 MM
CameraZWO 071 Pro @-10C
CorrectorExplore Scientific HR coma corrector
FiltersAstronomik L-1 - UV IR Block Filter
Exposure75x180s, Gain 134, bin 1x1,