Pi Arietis
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Aries[1] |
Right ascension | 02h 49m 17.55924s[2] |
Declination | +17° 27′ 51.5168″[2] |
Apparent magnitude (V) | 5.314[3] |
Characteristics | |
Spectral type | B6 V + A0 V + F8 V[4] |
U−B color index | −0.47[5] |
B−V color index | −0.06[5] |
Astrometry | |
Radial velocity (Rv) | +8.8±0.9[6] km/s |
Proper motion (μ) | RA: +2.60 mas/yr[2] Dec.: −14.10 mas/yr[2] |
Parallax (π) | 4.18±0.69 mas[2] |
Distance | approx. 800 ly (approx. 240 pc) |
Absolute magnitude (MV) | −1.56[1] |
Details | |
Mass | 4.4+0.55 −0.51[3] M☉ |
Luminosity | 538[1] L☉ |
Surface gravity (log g) | 4.5±0.25[3] cgs |
Temperature | 16,000±1,000[3] K |
Rotational velocity (v sin i) | 70[7] km/s |
Age | 13+9 −6[3] Myr |
Other designations | |
π Ari, 42 Arietis, NSV 944, BD+16°355, GC 3378, HD 17543, HIP 13165, HR 836, SAO 93127, PPM 118581[8] | |
Database references | |
SIMBAD | data |
Pi Arietis is a multiple star system in the northern constellation of Aries. Its name is a Bayer designation that is Latinized from π Arietis, and abbreviated Pi Ari or π Ari. Based upon parallax measurements made during the Hipparcos mission, this system is approximately 800 light-years (250 parsecs) distant from Earth,[2] and has an apparent visual magnitude of 5.314.[3] This is bright enough to be faintly seen with the naked eye. The position of this system near the ecliptic means it is subject to lunar occultation.[9]
The primary member of this system is an intermediate-mass,[3] B-type main sequence star with a stellar classification of B6 V. It is a close, single-lined[10] spectroscopic binary with an orbital period of 3.854 days, an eccentricity of 0.04, and a combined visual magnitude of 5.30. At an angular separation of 3.28 arcseconds is a magnitude 8.46 A-type main sequence star with a classification of A0 Vp. Finally, a fourth member of the system is a magnitude 11.0 F-type main sequence star with a classification of F8V at an angular separation of 25.2 arcseconds from the primary.[4]
Name
[edit]This star, along with δ Ari, ε Ari, ζ Ari, and ρ3 Ari, were Al Bīrūnī's Al Buṭain (ألبطين), the dual of Al Baṭn, the Belly.[11] According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Buṭain were the title for five stars : δ Ari as Botein, π Ari as Al Buṭain I, ρ3 Ari as Al Buṭain II, ε Ari as Al Buṭain III dan ζ Ari as Al Buṭain IV.[12]
In Chinese, 左更 (Zuǒ Gēng), meaning Official in Charge of the Forest, refers to an asterism consisting of π Arietis, ν Arietis, μ Arietis, ο Arietis and σ Arietis.[13] Consequently, the Chinese name for π Arietis itself is 左更五 (Zuǒ Gēng wu, English: the Fifth Star of Official in Charge of the Forest.)[14]
References
[edit]- ^ a b c Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
- ^ a b c d e 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, S2CID 18759600.
- ^ a b c d e f g Gullikson, Kevin; et al. (August 2016), "The Close Companion Mass-ratio Distribution of Intermediate-mass Stars", The Astronomical Journal, 152 (2): 13, arXiv:1604.06456, Bibcode:2016AJ....152...40G, doi:10.3847/0004-6256/152/2/40, S2CID 119179065, 40.
- ^ a b 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ a b Crawford, D. L.; et al. (1971), "Four-color, H-beta, and UBV photometry for bright B-type stars in the northern hemisphere", The Astronomical Journal, 76: 1058, Bibcode:1971AJ.....76.1058C, doi:10.1086/111220.
- ^ Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
- ^ Abt, Helmut A.; et al. (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590.
- ^ "pi. Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-08-07.
- ^ Herr, Richard B. (April 1969), "Identification List of Spectroscopic and Eclipsing Binaries Subject to Occultations by the Moon", Publications of the Astronomical Society of the Pacific, 81 (479): 105, Bibcode:1969PASP...81..105H, doi:10.1086/128748.
- ^ Chini, R.; et al. (2012), "A spectroscopic survey on the multiplicity of high-mass stars", Monthly Notices of the Royal Astronomical Society, 424 (3): 1925–1929, arXiv:1205.5238, Bibcode:2012MNRAS.424.1925C, doi:10.1111/j.1365-2966.2012.21317.x, S2CID 119120749.
- ^ Allen, R. H. (1963), Star Names: Their Lore and Meaning (Reprint ed.), New York, NY: Dover Publications Inc, p. 83, ISBN 0-486-21079-0, retrieved 2010-12-12.
{{citation}}
: CS1 maint: ignored ISBN errors (link) - ^ Rhoads, Jack W. (November 15, 1971), "Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars", Jet Propulsion Laboratory, California Institute of Technology, retrieved 2025-05-07.
- ^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
- ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 21 日 Archived 2011-05-22 at the Wayback Machine