Psi Tauri


Psi Tauri
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Taurus
Right ascension 04h 07m 00.45697s[1]
Declination +29° 00′ 04.7084″[1]
Apparent magnitude (V) +5.22[2]
Evolutionary stage main sequence
Spectral type F1 V[3]
U−B color index −0.01[2]
B−V color index +0.34[2]
Radial velocity (Rv)+9.15±0.42[1] km/s
Proper motion (μ) RA: −91.40[4] mas/yr
Dec.: +7.58[4] mas/yr
Parallax (π)36.2231 ± 0.1714[1] mas
Distance90.0 ± 0.4 ly
(27.6 ± 0.1 pc)
Absolute magnitude (MV)3.01[5]
Mass1.59[5] M
[1] R
Luminosity5.12±0.03[1] L
Surface gravity (log g)4.36±0.14[5] cgs
[1] K
Metallicity [Fe/H]−0.20[6] dex
Rotational velocity (v sin i)45.4±2.3[7] km/s
Age1.435[5] Gyr
Other designations
ψ Tau, 42 Tau, BD+28° 619, FK5 2295, HD 25867, HIP 19205, HR 1269, SAO 76461[8]
Database references

Psi Tauri, which is Latinized from ψ Tauri, is a solitary[9] star in the zodiac constellation of Taurus. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude of +5.22.[2] The distance to this system, as determined using an annual parallax shift of 36.2 mas as seen from the Earth,[4] is 90 light years. It is drifting further away with a radial velocity of +9 km/s.[1]

This object is an F-type main sequence star with a stellar classification of F1 V,[3] which indicates it is undergoing core hydrogen fusion. It is about 1.4 billion years old and is spinning with a projected rotational velocity of 45 km/s.[7] The star has 1.6 times the mass[5] and radius of the Sun.[1] It is radiating 4.8 times the Sun's luminosity from its photosphere at an effective temperature of 7,088 K.[5]


  1. ^ a b c d e f g h i Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d Landolt, A. U. (October 1967), "Photoelectric UBV sequences in Taurus", Astronomical Journal, 72: 1012–1018, Bibcode:1967AJ.....72.1012L, doi:10.1086/110377.
  3. ^ a b Cowley, Anne; Fraquelli, Dorothy (February 1974), "MK Spectral Types for Some Bright F Stars", Publications of the Astronomical Society of the Pacific, 86 (509): 70, Bibcode:1974PASP...86...70C, doi:10.1086/129562.
  4. ^ a b c van Leeuwen, F. (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.
  5. ^ a b c d e f David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
  6. ^ Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191, S2CID 118577511.
  7. ^ a b Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics, 542: A116, arXiv:1204.2459, Bibcode:2012A&A...542A.116A, doi:10.1051/0004-6361/201118724, S2CID 53666672.
  8. ^ "psi Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-30.
  9. ^ 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.