Tau1 Arietis
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aries[1] |
| Right ascension | 03h 21m 13.62462s[2] |
| Declination | +21° 08′ 49.4390″[2] |
| Apparent magnitude (V) | 5.27[3] |
| Characteristics | |
| Evolutionary stage | Main sequence (90% chance)[4] |
| Spectral type | B5 IV[5] |
| U−B color index | −0.53[3] |
| B−V color index | −0.06[3] |
| Astrometry | |
| Radial velocity (Rv) | +14[6] km/s |
| Proper motion (μ) | RA: +25.651[2] mas/yr Dec.: −19.850[2] mas/yr |
| Parallax (π) | 6.1786±0.2066 mas[2] |
| Distance | 530 ± 20 ly (162 ± 5 pc) |
| Absolute magnitude (MV) | −0.66[1] |
| Details | |
| Mass | 5.0±0.1[7] M☉ |
| Radius | 4.45[2] R☉ |
| Luminosity | 234[1] L☉ |
| Surface gravity (log g) | 3.68[2] cgs |
| Temperature | 12,606[2] K |
| Metallicity [Fe/H] | −0.63[2] dex |
| Rotational velocity (v sin i) | 30[8] km/s |
| Age | 54.8±5.4[7] Myr |
| Other designations | |
| τ1 Ari, 61 Arietis, BD+20 543, FK5 1094, HD 20756, HIP 15627, HR 1005, SAO 75886, PPM 92422, WDS J03212+2109A[9] | |
| Database references | |
| SIMBAD | data |
Tau1 Arietis is a triple star system[10] in the northern constellation of Aries. Its name is a Bayer designation that is Latinized from τ1 Arietis, and abbreviated Tau1 Ari or τ1 Ari. Based upon an annual parallax shift of 6.1786 mas, it is approximately 530 light-years (162 parsecs) distant from Earth. The combined apparent visual magnitude is 5.27,[3] making it faintly visible to the naked eye.
The Tau1 Arietis system contains three stars. The inner pair form an eclipsing binary system, with the brightness of the pair decreasing by 0.06 in magnitude during an eclipse of the primary.[12] This is a detached binary with an orbital period of 2.2035601139 days.[4] The third stellar component is located at an angular separation of 0.810 arcseconds and has a magnitude of 8.17.[10]
The primary component is a subgiant star with a stellar classification of B5 IV,[5] which suggests it is close to exhausting the supply of hydrogen at its core and evolving away from the main sequence. It has five times the mass of the Sun[7] with about four times the Sun's radius.[2] This star is around 55 million years old[7] and is spinning with a projected rotational velocity of 30 km/s.[8] It is radiating 234 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 12,606 km/s.[2] Based on photometric data, the stellar light curve displays variability with periods of 1.105 and 1.492 days.[13] It has been classified as a candidate slowly pulsating B-type star.[14]
This system is a member of the Cas-Tau OB association of stars that share a common motion through space.[15]
References
[edit]- ^ a b c d 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 f g h i j k Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d 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.
- ^ a b Avvakumova, E. A.; et al. (October 2013), "Eclipsing variables: Catalogue and classification" (PDF), Astronomische Nachrichten, 334 (8): 860, Bibcode:2013AN....334..860A, doi:10.1002/asna.201311942, hdl:10995/27061, retrieved 2025-05-09.
- ^ a b Lesh, Janet Rountree (December 1968), "The Kinematics of the Gould Belt: an Expanding Group?", Astrophysical Journal Supplement, 17: 371, Bibcode:1968ApJS...17..371L, doi:10.1086/190179.
- ^ Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick (eds.), Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, vol. 30, University of Toronto: International Astronomical Union, p. 57, Bibcode:1967IAUS...30...57E.
- ^ a b c d Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
- ^ a b 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.
- ^ "tau01 Ari", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2012-08-11.
- ^ 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.
- ^ MAST: Barbara A. Mikulski Archive for Space Telescopes, Space Telescope Science Institute, retrieved 8 December 2021.
- ^ Malkov, O. Yu.; et al. (February 2006), "A catalogue of eclipsing variables", Astronomy and Astrophysics, 446 (2): 785–789, Bibcode:2006A&A...446..785M, doi:10.1051/0004-6361:20053137, hdl:10995/73280.
- ^ Sangaralingam, Vinothini; Stevens, Ian R. (December 2011), "STEREO TRansiting Exoplanet and Stellar Survey (STRESS) - I. Introduction and data pipeline", Monthly Notices of the Royal Astronomical Society, 418 (2): 1325–1334, Bibcode:2011MNRAS.418.1325S, doi:10.1111/j.1365-2966.2011.19581.x.
- ^ Shi, Xiang-dong; Qian, Sheng-bang; Zhu, Li-ying; Liu, Liang; Li, Lin-jia; Zang, Lei (April 2023), "Observational Properties of 155 O- and B-type Massive Pulsating Stars", The Astrophysical Journal Supplement Series, 265 (2), id. 33, arXiv:2412.03821, Bibcode:2023ApJS..265...33S, doi:10.3847/1538-4365/acba91.
- ^ de Zeeuw, P. T.; et al. (January 1999), "A HIPPARCOS Census of the Nearby OB Associations", The Astronomical Journal, 117 (1): 354–399, arXiv:astro-ph/9809227, Bibcode:1999AJ....117..354D, doi:10.1086/300682, S2CID 16098861.
