M52 - Scorpion Cluster
| Polish version is here |
Messier 52 or the Scorpion Cluster, also cataloged as NGC 7654, is an open cluster located in the constellation Cassiopeia. Discovered by Charles Messier on 7 September 1774 while he was tracking a comet, M 52 stands as a textbook example of a young, compact open cluster whose brightness and position against the Milky Way make it an appealing target for observation.
The cluster lies roughly 3,000 to 7,000 light-years from Earth, and astronomers put its age at a little more than 35 million years—remarkably young on a cosmic timescale. It contains several hundred stars, including numerous B-type giants and supergiants, along with many young main-sequence suns. Its integrated visual magnitude is about 6.9 mag, so under dark skies a good pair of binoculars will reveal it. Covering some 13 arcminutes of sky, M52 corresponds to a physical diameter of roughly 11 to 26 light-years, depending on the distance.
Observations
26 May 2025, around 11:00 PM — Katowice, Poland
urban conditions, very high light pollution
A clear night — despite heavy skyglow — allowed for the following photographic capture.
Messier 52 exemplifies a young, massive-star-rich open cluster that offers not only aesthetic rewards to visual observers but also valuable data for astrophysical research. Returning to this object regularly can sharpen one’s observational skills and yield fresh insights — especially in studies of cluster evolution and internal dynamics.
Photo 1 Parameters:
- Total exposure time: 40 minutes (stack of 20 RAW frames at 120s each, using an appropriate number of dark, bias, and flat frames)
- Canon EOS 600D
- ISO: 1600
- Achromatic refractor Messier AR-152S (152/760), prime focus exposure
- A filter was used to reduce the effects of artificial light pollution and atmospheric glow
- Mount: equatorial mount with tracking, aligned using the drift method and controlled by a custom-built system.
Further readings:
- Adam L., Imaging the Messier Objects Remotely from Your Laptop, The Patrick Moore Practical Astronomy Series, Springer, 2018, p. 241
- Bonatto C., Bica E., Methods for improving open cluster fundamental parameters applied to M 52 and NGC 3960, Astronomy and Astrophysics, 2006, 455(3), pp. 931-942
- Trumpler R. J., Preliminary results on the distances, dimensions and space distribution of open star clusters, Lick Observatory Bulletin, 1930, 420, pp. 154-188
Marek Ples