M50 — Heart-Shaped Cluster
Open Cluster in Monoceros
About
An open cluster in Monoceros, about 2,900 light-years away, with roughly 500 confirmed member stars. Its outline is sometimes called heart-shaped. Recent work suggests it is really two sub-clusters, which would make it a binary cluster.
Imaging tips
- Spans 16′, so it fills about half the frame at 1,510–2,520 mm on APS-C.
- One imager got a clean result from only an hour of 30-second subs under Bortle 4 skies, with no filter: a loose cluster is forgiving.
- It is rarely imaged because it has few features, so framing matters; a faint small nebula sits between the cluster and a corner of that imager's frame.
- It lies about 8° north and 3° east of Sirius, which makes it easy to find, though Sirius's glare can wash out the view in the eyepiece.
- Best in December and January; it stays below 32° altitude from 50°N.
Facts
- Size
- 16′
- Magnitude
- 5.9
- Coordinates
- RA 7h 2.9m, Dec −8° 22′
- Framing, APS-C
- 1510–2520 mm
- Framing, full frame
- 2320–3870 mm
- Best months
- Jan, Dec
- Peak altitude
- 32° from 50°N, 47° from 35°N