Cr249
Open Cluster in Centaurus
About
Collinder's 1931 catalogue lists number 249 as the same object as IC 2944, a cluster of young stars lighting a hydrogen cloud in Centaurus, about 6,500 light-years away. The bird shape of its brightest part gave the Running Chicken name. Dark globules, first noted by Thackeray in 1950, dot the glow.
Imaging tips
- Sources give the glowing region as 40 × 20′ and as about 75′, so frame wide or plan a mosaic; a long focal length would crop it.
- RGB alone leaves the region almost featureless; narrowband (Hα, OIII) brings out depth.
- One imager built a 54-hour two-panel mosaic: 25 h 20 min Hα, 22 h 40 min OIII and 6 h RGB.
- IC 2948 belongs to the same hydrogen complex, so it can share a wide field or a mosaic panel.
- Best February to April, but it never rises from 50°N or 35°N: a southern-hemisphere target.
Facts
- Size
- 18.5′
- Magnitude
- 6.7
- Coordinates
- RA 11h 38.6m, Dec −63° 23′
- Framing, APS-C
- 1310–2180 mm
- Framing, full frame
- 2010–3340 mm
- Best months
- Feb, Mar, Apr
- Peak altitude
- never rises from 50°N, never rises from 35°N
Nearby
- C100 · 2.2′ away