H-NGC2266
Open Cluster in Gemini
About
A compact open cluster in Gemini, also Melotte 50, about 9,100 light-years away and around 1.2 billion years old. Its membership tops 190 stars, mostly main-sequence, and 11 of them are red giants. William Herschel found it in 1785.
Imaging tips
- Sources give 5–7′ across, so use a long focal length: 3460–5770 mm on APS-C puts it at a third to half of the frame.
- Faint at 22.4 mag/arcsec². One imager shot red, green and blue only, 2-minute subs, with a 14-inch f/11 scope at 3,940 mm.
- That imager logged 35 red, 33 green and 29 blue subs, and noted a triangular shape and a few distant galaxies in the field.
- Best around December and January; it peaks near 67° from 50°N, high in the sky.
Facts
- Size
- 7′
- Magnitude
- 9.5
- Coordinates
- RA 6h 43.3m, Dec +26° 59′
- Framing, APS-C
- 3460–5770 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Jan, Dec
- Peak altitude
- 67° from 50°N, 82° from 35°N