NGC/IC Project Restoration Effort

(This is a very very beta version)

NGC2251

 

Basic Information


Location and Magnitude


Right Ascension: 6:34:38.4
Declination: +8:21:59
Constellation: MON
Visual Magnitude: 7.3

Historic Information


Discoverer: Herschel W.
Year of discovery: 1783
Discovery aperture: 18.7

Observational


Summary description: Cl, vL, E, Ri, lC
Sub-type: III2p

Steve's Notes

===== NGC 2251 18" (3/4/08): at 175x, this is a fairly striking cluster that includes a fairly rich 6' string oriented N-S. The string contains ~20 stars including a mag 10.5/11.5 double at 5" (Barton 2120). The brightest star in near the geometric center and is part of second group of ~20 stars with several in a 2' loop. The bright star is a mag 9.5/11.5 pair at 9". Finally, on the north side is a small string of a half-dozen stars oriented E-W. 17.5" (3/12/94): about 40 stars mag 10.5-14 in an 11'x4' fairly rich string NW-SE. Includes about 10 brighter mag 11 stars. The brightest mag 9.5 star is part of a small, roundish subgroup on the west side and is a pleasing double with components mag 9.5/12 at 10". This subgroup has three brighter stars and 15 faint stars mostly west of the double. The main string is fairly uniform except for an empty 3' gap SE of the mag 9.5 star. Located 5' NW of the cluster is an isolated mag 10 star which appears to be a field star. 17.5" (2/1/92): 35 stars mag 10-14 in 12'x6' string NNW-SSE, bright, moderately large, fairly rich but not dense. Consists of 3 main subgroups. The western group is 2' diameter and includes a close double star 10/12 at 10". The NW group is 3' diameter and includes two mag 11 stars with three mag 13 stars between. The SE group is largest and includes 15 stars in a 6' string very elongated N-S with a close double star.