Category: Open cluster

IC 2602 Southern Pleiades

Southern Pleiades, just like the northern Pleiades is an open cluster, located in the constellation Carina. Unlike the northern sibling, this cluster is not associated with nebulosity. However, some dark nebulae can be found around. This is because the cluster is located just a few degrees from the galactical equator.

TelescopeSharpstar 94EDPH
Aperture94 mm
Focal length414 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, QHY Mini Guide Scope
CameraZWO 2600MM @-10°C
CorrectorF4.4 Quad Reducer
FiltersAntlia LRGB
Exposure43x180s RGB, Gain 100, bin 1x1,
Date2022-06-01

Norma Star Cloud

The constellation Norma is surrounded by the constellations Scorpius, Ara, Lupus, and Triangulum Australe. It forms the Milky Way’s Norma arm. Therefore there are a lot of stars anywhere you look. I wanted to capture something other than the nebulae, galaxies, or clusters. And this is exactly what I managed. This star cloud is not visible even from southern Europe, so I included it in the capture plan for my trip to Namibia.

In order to resolve the stars properly and fit the whole start cloud in the field of view, I used RedCat 51 telescope, having a focal length of 250 mm.

TelescopeWilliam Optics RedCat 51/250 f4.9
Aperture51 mm
Focal length250 mm
MountiOptron Skyguider Pro
AutoguidingZWO 178MM, QHY Mini Guide Scope 30/130 mm
CameraZWO ASI071 MC Pro @-10 °C
Filtersnone
Exposure40x180s, gain 95
Date2022-06-01

IC1805 Heart Nebula and IC1848 Soul Nebula

One of the last deep space objects I captured on Crete are two visually large nebulae. And these are IC1805 Heart Nebula and IC 1848 Soul Nebula. Both are very dim objects, therefore I set the shutter speed of the Canon EOS 6Da camera to 3 minutes and let it capture the light shooting from the constellation Perseus the whole night long. Even NGC 884 869 Double Cluster fit in the field of view.

Technical details:

LensAskar FMA180 F4.5
CameraCanon EOS 6Da
MountiOptron Skyguider Pro
Exposure50x180s, ISO 1600
Date2021-07-12

M24 Sagittarius Star Cloud

Messier 24 is a spiral arm of our galaxy located in the constellation Sagittarius. The region is heavily populated by the stars, which makes you think how big our home galaxy Milky Way is. I captured it already a few years back, but it would be a pity not to recapture this magnificent star cloud again with a slightly shorter focal length and under the dark skies of Fuerteventura.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure75x120s, Gain 94, bin 1x1,
Date2020-07-21

M7 Ptolemy cluster

Messier 7, sometimes called the Ptolemy Cluster, is an open cluster located in between constellations Sagittarius and Scorpius. The cluster is visually located on the galactic plane of the Milky Way, therefore there are many stars in the background. The cluster is badly visible from Central Europe. Much better opportunities to observe or photograph this cluster have astronomers or astrophotographers in southern countries. My last attempt to capture it in Greece was constantly disturbed by the weather, therefore when I was again in the South, specifically at Fuerteventura, I didn’t hesitate and recapture this beautiful cluster.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure64x180s, Gain 94, bin 1x1,
Date2020-07-21

M8 Lagoon Nebula, M20 Trifid Nebula

These two magnificent nebulae are located visually close to each other in the constellation Sagittarius. This means we are looking in the direction of the galactic core of the Milky Way. Trifid Nebula (up left) is a combination of a reflection nebula (blue part), a dark nebula (brown clouds), an emission nebula (red region), and a star cluster. On the other hand, the Lagoon nebula (right side) is an emission nebula – a giant cloud of ionized HII gas. Due to the very low southern declination, it’s challenging to photograph these deep space objects from my home place in Central Europe. Therefore every time I travel south, I take the opportunity and recapture these nebulae. My first attempt of M20 was made with a focal length of 917 mm, the second one with 630 mm and now I used a gentle focal reducer. A focal length of 570 mm allowed me to fit both nebulae into the field of view of the APS-C sensor size. The picture is an integration of 213 minutes, taken under the dark skies of Fuerteventura.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure71x180s, Gain 94, bin 1x1,
Date2020-07-18

M44 Beehive Cluster

Messier 44, sometimes called Beehive cluster, is visually one of the biggest open cluster, which can be observed from northern hemisphere. Previous picture, taken 3 year ago, was done with focal length 1000 mm. Now I changed the strategy and used only 630 mm. I think this was a good idea and whole cluster is perfectly framed.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure76x180s, Gain 94, bin 1x1,
Date2020-03-46

M48 Open Cluster

Telescope is out after long time. My main targets for this night are some galaxies in constellation Leo, but I have to wait for these galaxies to cross the meridian (line splitting west and east). By browsing in planetarium software I found one object, which can fill the gap – it was the open cluster M48. Open cluster usually don’t need super dark skies, therefore I can capture them during the evening, when there is still strong light pollution. My previous picture was taken by much longer focal length, therefore the cluster covered nearly whole field of view. This time the background if filled by many stars, which are not members of this cluster.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure76x180s, Gain 94, bin 1x1,
Date2020-03-18

Double Cluster NGC869 and NGC884

Two clusters visually close to each other can be located between constellations Perseus and Cassiopeia.  The clusters are relatively young (12 million years) and they are 2700 light-years far from Earth.

The picture was captured during my travel to Karpathos where I had only single wind free night.

I know, the composition should be turned by 90°. I just simply forgot to twist the camera.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-5°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure28x180s, Gain 94, bin 1x1,
Date2019-09-03

M93 Open Cluster

Messier 93 is an open cluster located in constellation Puppis and it is about 3400 light-year away from Earth. My previous attempt to capture this object was not so successful, because M93 doesn’t rise far from horizon in Central Europe. On La Palma is the situation different, but only if the weather allows it. I was partially lucky and a hole between the clouds appeared and I got 44 minutes opportunity to capture this cluster properly.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-10°C
CorrectorExplore Scientific HR
FiltersAstronomik L-1 - UV IR Block Filter
Exposure22x120s, Gain 94, bin 1x1,
Date2019-04-28

M93 Open Cluster

Messier 93 is an open cluster located in constellation Puppis and it is about 3400 light-year away from Earth. The cluster is one of those deep space objects, which I cannot see from my home, therefore I had to pack the gear and enjoy starry night outside. Compared to my previous attempt, I took the laser collimator with me and waited sufficiently long the temper the telescope. Well I was surprised that the stars are slightly oval and there is blue halo on one side and red one on the other side of nearly each star. I was speculating if there is something wrong with the optics, but then I realized that this object has very low declination (it’s not far from horizon), therefore it’s exposed to atmosphere refraction/dispersion. This means that the light must pass through the thick layer of an air. In this case the atmosphere works as a lens and bends red and blue light differently. The effect is described here or here.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-20°C
CorrectorExplore Scientific HR
FiltersHutech IDAS LPS-D2
Exposure30x60s, Gain 136, bin 1x1,
Date2019-03-27

M41 Open Cluster

In order to complete the Messier Catalogue and capture all of its deep space objects, I have to pack the telescope, mount, camera, cables and batteries and set it up somewhere in the nature with better view. Most of the objects I am able to capture from home, but some of them have very low declination (not far above the horizon) and I cannot see them from my terrace, because there is a hill direction south.

Messier 41, open cluster in constellation Canis Major is one of them.  So, I packed my car and went to collect some photons. At least I got the opportunity to test my new mount Avalon M-Zero, which replaced my previous portable mount iOptron CEM25P. The old portable mount was working well, but due to conventional equatorial design, one needs a counterweight, which was in this case 5 kg. This means 1/3 of the total weight. M-Zero is basically single fork mount, which utilizes the weight of the motors and housing as a counterweight. Moreover, M-Zero uses belts and pulleys, which means zero backlash. I can confirm – it works very well. I can save few kgs in my case during my next travel expedition.

The night was cold and since I don’t do the astrophotography in the nature frequently, I faced some issues. First, the portable telescope lost the collimation and I didn’t have the laser collimator with me. Second, I started to photograph before the telescope reached the thermal equilibrium, therefore there was a focus drift. This is definitely not my best picture, but I can at least check another Messier object from the list.

Technical details

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-20°C
CorrectorExplore Scientific HR
FiltersHutech IDAS LPS-D2
Exposure39x60s, Gain 136, bin 1x1,
Date2019-02-12

M37 Open Cluster

Messier 37 is the largest and the brightest open cluster in constellation Auriga. Visually, it has two deep space neighboring open clusters M36 and M38. The cluster was discovered by Giovani Battista Hodierna in 1654 and catalogued by Charles Messier in 1764. The cluster contains a lot of red giant stars and it is approximately 4500 light-year away from Earth.

This is the second deep space object, which I captured in a single night. The clouds rolled in, therefore I was able to capture only 30 pictures, 60 second each.

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorExplore Scientific HR coma corrector
FiltersHutech IDAS LPS-D2
Exposure30x60s, Gain 94, bin 1x1,
Date2019-02-08

M36 Open Cluster

Messier 36 is an open cluster located in constellation Auriga, not far from the bright star Capella. The cluster is approximately 4000 light-years from Earth and it has diameter 14 light-years. There are another two open clusters in the vicinity. Specifically it is M38 (north-west) and M37 (south-east).

The picture is a stack of 50 images, each has 60 s exposure time, which means less than hour of the integration time. Another Messier object was captures. I hope, I will finish the whole Messier catalogue this year.

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorExplore Scientific HR coma corrector
FiltersHutech IDAS LPS-D2
Exposure50x60s, Gain 94, bin 1x1,
Date2019-02-08

M46 M47 Open Clusters

Messier 46 (left) and Messier 47 are open clusters located in constellation Puppis. Visually, these clusters are quite close to each other and both fit in the field of view of my smallest telescope. Visual distance is not the real distance, because M46 in approximately 5000 light-years away and M47 is much closer, only 1600 light-years away.

M46 contains roughly 500 members and small planetary nebula called NGC2438 can be found there.

The picture is a stack of 22 pictures, 2 minutes exposure each, which means 44 minutes in total. Unfortunately, my telescope was not properly collimated, therefore the stars are elongated in the upper left corner. Well, I must say that this was the first and the last night in January without clouds, therefore I did not get the chance to recapture this deep space object.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length630 mm
MountAvalon M-Zero
AutoguidingZWO 174MM, OAG
CameraZWO 071 Pro @-20°C
CorrectorExplore Scientific HR
FiltersHutech IDAS LPS-D2
Exposure22x120s, Gain 94, bin 1x1,
Date2019-01-30

M103 Open Cluster


Messier 103 is an open cluster located in constellation Cassiopeia. With its distance 8500 light-year from Earth, this cluster is one of the most distant clusters from Messier’s catalogue.

The picture is a stack of 56 pictures, each 2 minutes long, i.e. nearly two hours of integration time. December is a month, which is rich with deep space objects, but it’s also rich with clouds. In whole December I got only single opportunity to take my telescope outside, therefore this is not the only deep space object, which I captured this night.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorTS-Optics 2" 3-element MaxField
FiltersHutech IDAS LPS-D2
Exposure56x120s, Gain 94, bin 1x1,
Date2018-12-13

M35 Shoe-Buckle Cluster

Messier 35 an open cluster located in constellation Gemini. The cluster is approximately 2800 light-year far from Earth and it contains roughly 200 stars.

Second open cluster NGC 2158 is located in the background (upper right part of the picture). I didn’t know that there is another cluster in field of view. If I would know it, I would change the composition of the picture.

This cluster was the last one out of four captured during single night. In the early morning I slewed to M35 and went to sleep. The camera captured 56 exposures, 3 minutes each, before the dawn arrived. This means nearly 3 hours of total exposure time.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length1000 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorTS-Optics 2" 3-element MaxField
FiltersHutech IDAS LPS-D2
Exposure56x180s, Gain 94, bin 1x1,
Date2018-11-18

 


M38 Open Cluster

Messier 38 is an open cluster located in constellation Auriga. It has diameter 25 light-years and it’s approximately 3500 light-year away from Earth.

I managed to capture two open clusters this night already (M39 and M34) and there is still one to go (M35). Therefore I didn’t dedicate a lot of time on M38 – this means that the picture is an integration of one hour of exposure time.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length950 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorTS-Optics 2" 3-element MaxField
FiltersHutech IDAS LPS-D2
Exposure20x180s, Gain 94, bin 1x1,
Date2018-11-18


M34 Open Cluster

After capturing M39 I slewed the telescope to another deep space object. Specifically to an open cluster Messier 39. This cluster is located in constellation Perseus and it is approximately 1400 light-years away from Earth and it has diameter roughly 24 light-years.

The picture is a stack of 72 two minute subframes, which means 144 minutes of total integration time.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length950 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorTS-Optics 2" 3-element MaxField
FiltersHutech IDAS LPS-D2
Exposure72x120s, Gain 94, bin 1x1,
Date2018-11-18


M39 Open cluster

Messier 39 is an open cluster located in constellation Cygnus and it’s only 825 light-year away from Eartch. The cluster is visually located on the galactic plane of the Milky Way, therefore there are so many stars in the background.

I already captured M39 two years ago, but with different camera and different coma corrector. This time I used slightly bigger sensor and brand new corrector TS MaxField. This corrector should reduce the focal length by 5% and also due to the larger sensor I got bigger field of view compared to my previous picture. However, the corrector is not capable of eliminate the coma fully and in the corners are the stars elongated. I spent some time by adjusting the tilt, but this obviously didn’t solve the problem. This means that the only corrector which is capable of eliminating the comatic aberration fully is Explore Scientific HR CC.

Technical details:

TelescopeNewton 254/1000 mm
Aperture254 mm
Focal length950 mm
MountGemini G53f
AutoguidingZWO 174MM, TS 60/240 mm
CameraZWO 071 Pro @-20°C
CorrectorTS-Optics 2" 3-element MaxField
FiltersHutech IDAS LPS-D2
Exposure58x180s, Gain 94, bin 1x1,
Date2018-11-18

Here is the analysis of the curvature by CCD Inspector. I already adjusted the tilt by integrated push-pull screws on ASI071, but there is still some room for improvements.