NGC 3766 (also known as Caldwell 97) is an open star cluster in the southern constellation Centaurus. It is located in the vast star-forming region known as the Carina molecular cloud, and was discovered by Nicolas Louis de Lacaille during his astrometric survey in 1751–1752.[2] At a distance of about 1745 pc,[3] the cluster subtends a diameter of about 12 minutes of arc.[4]
| NGC 3766 | |
|---|---|
 NGC 3766 image taken with the MPG/ESO 1.2-metre telescope at the La Silla Observatory[1] Credit: ESO | |
| Observation data (J2000 epoch) | |
| Right ascension | 11h 36.1m |
| Declination | −61° 37′ |
| Distance | 5.5 kly |
| Apparent magnitude (V) | 5.3 |
| Apparent dimensions (V) | 12.0′ |
| Physical characteristics | |
| Radius | 9.6 ly |
| Easy to view via binoculars or telescope | |
| Other designations | NGC 3766, Caldwell 97, Collinder 248, Melotte 107, Dunlop 289, Lacaille III.7, C1133-613 |
| Associations | |
| Constellation | Centaurus |
There are 137 listed stars, but many are likely non-members, with only 36 having accurate photometric data.[5] It has a total apparent magnitude of 5.3 and integrated spectral type of B1.7.[3] NGC 3766 is relatively young, with an estimated age of log (7.160) or 14.4 million years,[4] and is approaching us at 14.8 km/s.[3] This cluster contains eleven Be stars, two red supergiants and four Ap stars.[5]
36 examples of an unusual type of variable star were discovered in the cluster. These fast-rotating pulsating B-type stars vary by only a few hundredths of a magnitude with periods less than half a day. They are main sequence stars, hotter than δ Scuti variables and cooler than slowly pulsating B stars.[6]
See also
editReferences
edit- ^ "New Kind of Variable Star Discovered". ESO Press Release. Retrieved 14 June 2013.
- ^ Jones, K. G. (March 1969). "The search for the nebulae - VI". Journal of the British Astronomical Association. 79: 213–222. Bibcode:1969JBAA...79..213J.
- ^ a b c "NGC 3766". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2013-06-13.
- ^ a b "WEBDA Astronomical Database". WEBDA Page for NGC 3766. Retrieved 2013-06-13.
- ^ a b "Webda Astronomical Database". WEBDA Page for NGC 3766a. Retrieved 2013-06-13.
- ^ Saio, H; Ekström, S; Mowlavi, N; Georgy, C; Saesen, S; Eggenberger, P; Semaan, T; Salmon, S. J. A. J (2017). "Period–luminosity relations of fast-rotating B-type stars in the young open cluster NGC 3766". Monthly Notices of the Royal Astronomical Society. 467 (4): 3864. arXiv:1702.02306. Bibcode:2017MNRAS.467.3864S. doi:10.1093/mnras/stx346.
External links
edit
Media related to NGC 3766 at Wikimedia Commons- NGC 3766 at SEDS
- Astrophotograph Link
- WEBDA Data on NGC 3766 by Lynga
- NGC 3766 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
