NGC 752
NGC 752 is an open cluster in the constellation Andromeda.
| NGC 752 | |
|---|---|
| Observation data: 2000.0 epoch | |
| Constellation | Andromeda |
| Right ascension | 01h 58m |
| Declination | +37° 50ˡ |
| Distance | 1.300 light years |
| Type | Open cluster |
| Apparent dimensions | 60ˡ |
| Apparent magnitude | 5.7 |
| Other designations | Melotte 12, Collinder 23 |
Discovery and observational data
NGC 752 is located less than 5° south-southwest of γ Andromedae and measures almost one degree in apparent diameter. It is a fairly bright open cluster whose stars are of apparent magnitude 8.9 and fainter.
Giovanni Hodierna probably observed NGC 752 in the mid 17th century but the cluster was definitively seen by Caroline Herschel in 1783. In 1786 William Herschel cataloged it. It carries a Trumpler classification of III,1,m indicating it shows a loose concentration of stars (III) that exhibit a narrow range in apparent magnitude (1) and the cluster as a whole contains about 50-100 stars (m). In fact, NGC 752 has about 60 member stars.
NGC 752 is a good object for amateur astronomers to observe with modest telescopes and is a popular target for binoculars as well.
Physical data
At an estimated age of 1.1 x 109 to 1.5 X 109 years, NGC 752 is among the older open clusters known. The most luminous star that is a member of the cluster is of spectral type A2 and apparent magnitude 8.96. Other type A stars are also found within the cluster.
References
- Frommert and Kronberg, SEDS, online at http://seds.org/messier/xtra/ngc/n0752.html
- NASA/IPAC Extragalactic Database