M52 — Scorpion Cluster
Open Cluster in Cassiopeia
About
A rich open cluster in Cassiopeia, about 4,600 light-years away and roughly 158 million years old. Charles Messier found it in 1774. Its core appears to contain little interstellar matter, and extinction is stronger in its southern half.
Imaging tips
- 13′ across: 1,860–3,110 mm on APS-C gives a comfortable fill with room for the surrounding star field.
- Imagers often include the Bubble Nebula (NGC 7635) too: one placed M52 and the nebula in opposite corners of a single frame for context.
- That framing mixes a star cluster with an Hα nebula: one imager added 30 minutes of Hα to 60 minutes of luminance, using a light-pollution filter.
- A narrowband two-panel mosaic of 184 subs of 3 minutes (9.2 hours) also took in the Lobster Claw Nebula (Sh 2-157).
- Best in August and September.
Facts
- Size
- 13′
- Magnitude
- 6.9
- Coordinates
- RA 23h 24.4m, Dec +61° 35′
- Framing, APS-C
- 1860–3110 mm
- Framing, full frame
- 2860–4760 mm
- Best months
- Aug, Sep
- Peak altitude
- 78° from 50°N, 63° from 35°N