Psi Sagittarii
| |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 19h 15m 32.42658s[1] |
| Declination | −25° 15′ 24.0569″[1] |
| Apparent magnitude (V) | +4.86 |
| Characteristics | |
| Spectral type | K2 III + A9 III + A3 V[2] |
| Astrometry | |
| Proper motion (μ) | RA: +45.50[1] mas/yr Dec.: −31.08[1] mas/yr |
| Parallax (π) | 10.93 ± 0.31[1] mas |
| Distance | 298 ± 8 ly (91 ± 3 pc) |
| Orbit[3] | |
| Period (P) | 7,319 d |
| Eccentricity (e) | 0.51 |
| Periastron epoch (T) | 2442418.795 JD |
| Argument of periastron (ω) (secondary) | 2.6° |
| Semi-amplitude (K1) (primary) | 10.0 km/s |
| Semi-amplitude (K2) (secondary) | 13.8 km/s |
| Details | |
| ψ Sgr A | |
| Mass | 2.10[4] M☉ |
| ψ Sgr Ba/Bb | |
| Mass | 1.70/2.70 M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Psi Sagittarii (ψ Sagittarii) is a triple star[6] system in the zodiac constellation of Sagittarius. The star system is 298 light years from Earth. The star system has a combined apparent magnitude of +4.86.
The inner pair of this triple star system, components Ba and Bb, have an orbital period of 10.78 days and an eccentricity of 0.47.[6] These in turn share an orbit with the primary, component A, having a period of 20 years and an eccentricity of 0.51.[3]
Name and etymology
According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, this star was titled as Al Kiladah.[7] This star, together with τ Sgr, ν Sgr, ω Sgr, 60 Sgr and ζ Sgr were Al Udḥiyy, the Ostrich's Nest.[8]
References
- 1 2 3 4 5 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752
, doi:10.1051/0004-6361:20078357. - ↑ Docobo, José A.; Andrade, Manuel (November 2006), "A Methodology for the Description of Multiple Stellar Systems with Spectroscopic Subcomponents", The Astrophysical Journal, 652 (1): 681−695, Bibcode:2006ApJ...652..681D, doi:10.1086/508053.
- 1 2 Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; et al. (2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy & Astrophysics, 424 (2): 727, Bibcode:2004A&A...424..727P, arXiv:astro-ph/0406573 , doi:10.1051/0004-6361:20041213.
- ↑ Tokovinin, A. (September 2008), "Comparative statistics and origin of triple and quadruple stars", Monthly Notices of the Royal Astronomical Society, 389 (2): 925−938, Bibcode:2008MNRAS.389..925T, doi:10.1111/j.1365-2966.2008.13613.x.
- ↑ "psi Sgr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-07-02.
- 1 2 Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, Bibcode:2008MNRAS.389..869E, arXiv:0806.2878 , doi:10.1111/j.1365-2966.2008.13596.x.
- ↑ Rhoads, Jack W. (November 15, 1971), Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars (PDF), California Institute of Technology: Jet Propulsion Laboratory, retrieved 2017-07-02.
- ↑ Allen, R. H. (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York: Dover Publications Inc. p. 355. ISBN 0-486-21079-0. Retrieved 2012-09-04.