NGC 6633
NGC 6633 is a large bright open cluster in the constellation Ophiuchus. Discovered in 1745-46 by Philippe Loys de Chéseaux, it was independently rediscovered by Caroline Herschel in 1783 and included in her brother William's catalog as H VIII.72.[1] Bright enough to be seen with the naked eye, the cluster is considered a fine object for binoculars or small telescopes.[2]
| NGC 6633 | |
|---|---|
 NGC 6633 (Stellarium image) (Roberto Mura) | |
| Observation data (J2000.0 epoch) | |
| Constellation | Ophiuchus |
| Right ascension | 18h 27.7m |
| Declination | 6° 34′ |
| Distance | 1.04 kly |
| Apparent magnitude (V) | 4.6 |
| Apparent dimensions (V) | 27′ |
| Physical characteristics | |
| Estimated age | 660 million years |
| Other designations | NGC 6633, De Cheseaux No. 3 H VIII.72, Cr 380, Mel 201 |
NGC 6633 is also known as the Tweedledum Cluster (paired with IC 4756 as Tweedledee), also as the Captain Hook Cluster.[3] It is also designated Collinder 380 or Melotte 201. Nearly as large as the full moon, the cluster contains about 30 stars and shines with a total magnitude of 4.6; the brightest star is of mag 7.6. Its age has been estimated at 660 million years.[1]
Map showing location of NGC 6633 (Roberto Mura)
References
- "NGC 6633". messier.seds.org. Retrieved 2020-10-05.
- Michael Bakich. "Open cluster NGC 6633, a complex of dark nebulae, and globular cluster M54". astronomy.com. Retrieved 2020-10-05.
- O'Meara, Stephen James (2007). Deep-Sky Companions: Hidden Treasures. Cambridge University Press. p. 457-458. ISBN 978-0521-83704-0.
External links
Media related to NGC 6633 at Wikimedia Commons- NGC 6633 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.