Alpha1 Capricorni
- For other star systems with this Bayer designation, see Alpha Capricorni.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Capricornus |
| Right ascension | 20h 17m 38.86987s[1] |
| Declination | −12° 30′ 25.5594″[1] |
| Apparent magnitude (V) | 4.27[2] |
| Characteristics | |
| Spectral type | G3 Ib[3] |
| U−B color index | +0.70[2] |
| B−V color index | +1.07[2] |
| Astrometry | |
| Proper motion (μ) | RA: 22.98 ± 0.32[1] mas/yr Dec.: 1.28 ± 0.28[1] mas/yr |
| Parallax (π) | 5.73 ± 0.33[1] mas |
| Distance | 570 ± 30 ly (170 ± 10 pc) |
| Details[3] | |
| Mass | 5.3 M☉ |
| Luminosity | 1,047 L☉ |
| Temperature | 5,300 K |
| Metallicity [Fe/H] | +0.22 dex |
| Rotational velocity (v sin i) | 7.3 km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Alpha1 Capricorni (α1 Cap, α1 Capricorni) is a double star in the southern constellation of Capricornus. It also has the traditional star name Prima Giedi or Algiedi Prima, and shares the name Algedi (from الجدي - al-jadii, meaning the goat) with α² Capricorni. It is approximately 690 light years from Earth.
α1 Capricorni has three faint companions within one arc-minute. The brightest of these is 10th magnitude and on this basis it has often been considered as a double star. The separation of the stars is increasing rapidly due to the high proper motion of the primary star. The Hipparcos satellite also detected a new very close companion, 0.6" away and four magnitudes fainter.[5]
The primary star is a yellow G3 supergiant with an apparent magnitude of +4.3. This star has 5.3 times the mass of the Sun and is radiating around 1,047 times the Sun's luminosity.[3]
In popular culture
The name Giedi Prime is used for a fictional planet in Frank Herbert's 1965 science fiction novel Dune. This Giedi Prime is a planet of the star 36 Ophiuchi B, and is the home world of the villainous House Harkonnen.[6]
References
- 1 2 3 4 5 van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv:0708.1752
. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. - 1 2 3 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D.
- 1 2 3 Smiljanic, R.; et al. (April 2006), "CNO in evolved intermediate mass stars", Astronomy and Astrophysics, 449 (2): 655–671, arXiv:astro-ph/0511329, Bibcode:2006A&A...449..655S, doi:10.1051/0004-6361:20054377
- ↑ Rumrill, H. B. (1936). "Star Name Pronunciation". Publications of the Astronomical Society of the Pacific. 48: 139. Bibcode:1936PASP...48..139R. doi:10.1086/124681.
- ↑ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
- ↑ Herbert, Frank (1965). Dune. ISBN 978-0441172719.