H-NGC2126
Open Cluster in Auriga
About
NGC 2126 is a small open cluster in Auriga, roughly 4,100 light-years away and about 1.3–1.6 billion years old. It is known for variable stars: TESS data in 2025 showed 25 cluster members that vary in brightness. William Herschel found it in 1787.
Imaging tips
- About 6′ across, so it is too small to frame: use a long focal length and a fine pixel scale.
- Faint for a cluster at 22.7 mag/arcsec² and magnitude 10.2, so plan on a good amount of total exposure.
- Herschel noted a 7th-magnitude star toward the north that does not seem to belong to the cluster.
- A faint background galaxy, Zwicky 232-5 at magnitude 15.4, lies about 7′ east of the cluster.
- Best in December and January; it passes almost overhead, reaching about 90° from 50°N.
Facts
- Size
- 6′
- Magnitude
- 10.2
- Coordinates
- RA 6h 2.6m, Dec +49° 53′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Jan, Dec
- Peak altitude
- 90° from 50°N, 75° from 35°N