Deneb
Deneb (α Cyg, α Cygni, Alpha Cygni) is the brichtest starn in the constellation Cygnus an ane o the vertices o the Simmer Triangle. It is the 19t brichtest starn in the nicht sky, wi an apparent magnitude o 1.25. A blue-white supergiant, Deneb is an aa ane o the maist luminous nearbi starns. However, its exact distance (an hence luminosity) haes been difficult tae calculate, so it is onywhaur atween 54,000 an 196,000 times as luminous as the sun.
 Cygnus, the constellation in which Deneb is locatit. | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus |
| Richt ascension | 20h 41m 25.9s |
| Declination | +45° 16′ 49″ |
| Apparent magnitude (V) | 1.25 |
| Chairactereestics | |
| Spectral type | A2 Ia[1] |
| U−B colour index | −0.24 |
| B−V colour index | +0.09 |
| Variable teep | Alpha Cyg |
| Astrometry | |
| Radial velocity (Rv) | −4.5 km/s |
| Proper motion (μ) | RA: 1.99[2][3] mas/yr Dec.: 1.95[2][3] mas/yr |
| Parallax (π) | 2.29 ± 0.32[2][3] mas |
| Distance | 802 + 66[4] pc |
| Absolute magnitude (MV) | −8.38[4] |
| Details | |
| Mass | 19 ± 4[4] M☉ |
| Radius | 203 ± 17[4] R☉ |
| Luminosity | 196,000 ± 32,000[4] L☉ |
| Surface gravity (log g) | 1.10 ± 0.05[4] cgs |
| Temperatur | 8,525 ± 75[4] K |
| Metallicity [Fe/H] | -0.25[4] dex |
| Rotational velocity (v sin i) | 20 ± 2[4] km/s |
| Ither designations | |
Ither names include Arided an Aridif, but these hae fallen oot o uise.
ReferencesEedit
- ↑ Garrison, R. F. (December 1993). "Anchor Points for the MK System of Spectral Classification". Bulletin of the American Astronomical Society. 25: 1319. Bibcode:1993AAS...183.1710G. Archived frae the original on 25 Juin 2019. Retrieved 4 Februar 2012.
- ↑ a b c Perryman, M. A. C.; Lindegren, L.; Kovalevsky, J.; et al. (Julie 1997). "The Hipparcos Catalogue". Astronomy and Astrophysics. 323: L49–L52. Bibcode:1997A&A...323L..49P. Explicit use of et al. in:
|last4=(help) - ↑ a b c van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- ↑ a b c d e f g h i
Schiller, F.; Przybilla, N. (2008). "Quantitative spectroscopy of Deneb". Astronomy & Astrophysics. 479 (3): 849–858. arXiv:0712.0040. Bibcode:2008A&A...479..849S. doi:10.1051/0004-6361:20078590.
Earlier data had yielded a luminosity of 54,000L☉ with a radius of 108R☉