| NGC 2546 | |
|---|---|
 NGC 2546 (taken from Stellarium) | |
| Observation data (J2000.0epoch) | |
| Right ascension | 08h 12m 19.7s[1] |
| Declination | −37° 39′ 40″[1] |
| Distance | A: 3,100 ly (950 pc) B: 4,700 ly (1,450 pc)[2] |
| Apparent magnitude (V) | 6.3[3] |
| Apparent dimensions (V) | 41′[3] |
| Physical characteristics | |
| Radius | 36 ly[4] |
| Other designations | NGC 2546,Cr 178, Dunlop 563, Lacaille II.4[5] |
| Associations | |
| Constellation | Puppis |
| See also:Open cluster,List of open clusters | |
NGC 2546 is a pair of independent but overlappingopen clusters[2] located in the southernconstellation ofPuppis. This grouping was discovered by French astronomerAbbe Lacaille in 1751-1752 from South Africa.[3][6] NGC 2546 is just visible to the naked eye as a fuzzy patch; the brightest component has anapparent visual magnitude of 6.44. The brighter members are readily resolved with a pair of 10×50 binoculars.[4]
Prior to 2020, this cluster had been poorly studied.[2] It was considered rather poor in stars but extensive with aTrumpler class of III 1m. The distribution was found to be elongated in a north–south direction with anangular size of 50′ x 25′. The cluster has an estimated 85 members brighter than visual magnitude 14.5. The age of the cluster was thought to be3×107 years.[7] ThreeAp stars were detected.[8] Cluster member AS Puppis is a candidate mass-losingAGB star.[9]
A 2020 study by A. J. Alejo and associates demonstrated that two physically distinct stellar groups occupy the region of NGC 2546. Membership in the two clusters could be distinguished by multiple parameters, with theradial velocity,spectral type, and reddening fromextinction being the most significant. The more populated cluster, designated NGC 2546A, is located at a distance of 3,100 ly (950 pc) and is about 180 Myr old with a half-member radius of 26 ly (8 pc). The second cluster, NGC 2546B, lies 4,700 ly (1,450 pc) from theSun and is less than 10 million years old with a half-member radius of 5.2 ly (1.6 pc). The angular separation between the center of two clusters is17′.[2]
Media related toNGC 2546 at Wikimedia Commons