NGC 2168 vs NGC 2632
Two open clusters of the northern winter and spring, differing mainly in scale. NGC 2632, the Beehive, reaches magnitude 3.10 across 108.60 arcminutes — nearly two degrees, or four times the width of the full Moon. NGC 2168 is fainter at 5.10 and more compact at 24.00 arcminutes. The Beehive's greater total light does not translate into a denser image: its surface brightness near 13.0 magnitudes per square arcminute falls behind the 11.7 of NGC 2168. Both resolve into individual stars in modest instruments, which makes surface brightness less decisive here than it is for nebulae, and the practical distinction is one of field of view.
Property comparison
| Property | NGC 2168 | NGC 2632 |
|---|---|---|
| Object type | Star Cluster | Star Cluster |
| Catalogue designation | NGC 2168 | NGC 2632 |
| Integrated magnitude | 5.10 | 3.10 |
| Apparent size | 24′ (24′) | 1.8° (108.6′) |
| Mean surface brightness | 11.7 mag/arcmin² | 13.0 mag/arcmin² |
| Position (J2000) | RA 6h, Dec +24° | RA 8h, Dec +19° |
| Sky region | Northern sky | Northern sky |
Mean surface brightness is derived from the integrated magnitude and the apparent diameter; higher values mean a fainter, more diffuse surface.
Full data for each object: NGC 2168 · NGC 2632
Key differences
Key Differences
- ◆ NGC 2632 is brighter at magnitude 3.10 against 5.10 for NGC 2168.
- ◆ NGC 2632 spans 108.60 arcminutes; NGC 2168 covers 24.00, roughly a quarter as wide.
- ◆ NGC 2168 has the higher surface brightness, near 11.7 magnitudes per square arcminute against 13.0.
- ◆ NGC 2632 is a naked-eye patch from a dark site; NGC 2168 generally requires binoculars.
- ◆ Declinations of +19° and +24° place both high in the northern sky within weeks of each other.