H-NGC2232
Open Cluster in Monoceros
About
A sparse, young open cluster in Monoceros, about 1,060 light-years away and around 31 million years old. At magnitude 3.9 it is a naked-eye object. Its members formed in the Gould Belt, the same region as the Orion Nebula cluster, and it counts among the Sun's closest open-cluster neighbours.
Imaging tips
- About 30′ across. At 810–1350 mm on APS-C (1240–2060 mm full frame) the cluster fits the frame.
- The cluster centres on 10 Monocerotis, a magnitude 5 star; the page lists 22 stars, many brighter than magnitude 10.
- Bright at 19.9 mag/arcsec², so broadband suits it: one imager used 12-inch f/5 optics and 5 three-minute subs per LRGB channel, 60 minutes total.
- Best around December and January; it peaks near 35° from 50°N.
Facts
- Size
- 30′
- Magnitude
- 3.9
- Coordinates
- RA 6h 27.5m, Dec −4° 45′
- Framing, APS-C
- 810–1350 mm
- Framing, full frame
- 1240–2060 mm
- Best months
- Jan, Dec
- Peak altitude
- 35° from 50°N, 50° from 35°N