C85 — Omicron Velorum Cluster
Open Cluster in Vela
About
IC 2391, the Omicron Velorum Cluster, about 30 hot young stars in Vela roughly 500 light-years away. Its age is about 50 million years. It shows to the naked eye, and its combined brightness is near magnitude 2.5.
Imaging tips
- Sources give its extent as 50–60′. At 480–810 mm on APS-C it fills a third to half of the frame; a lens that covers about a degree leaves room around it.
- One backyard image under Bortle 9 skies added Hα data to LRGB to bring out Gum 12, a faint nebula far behind the cluster.
- The open cluster NGC 2669, about 14′ across, appears in the same wide frame in that image.
- A 130 mm f/6.3 refractor produced a clean result in 3 h 45 min of LRGB at 3-minute subs.
- Best in January and February, but it never rises from 50°N and peaks near 2° from 35°N.
Facts
- Size
- 50′
- Magnitude
- 2.5
- Coordinates
- RA 8h 40.6m, Dec −53° 2′
- Framing, APS-C
- 480–810 mm
- Framing, full frame
- 740–1240 mm
- Best months
- Jan, Feb
- Peak altitude
- never rises from 50°N, 2° from 35°N