Phi Gruis, Latinised from φ Gruis, is a solitary,[7] yellow-white hued star in the southern constellation of Grus, near the eastern constellation border with Phoenix. It is faintly visible to the naked eye with an apparent visual magnitude of +5.49.[2] Based upon an annual parallax shift of 29.3 mas as seen from the Earth,[8] it lies at a distance of 111 light years from the Sun. The star is drifting further away with a radial velocity of +15 km/s.[1]

Phi Gruis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Grus
Right ascension 23h 18m 09.88466s[1]
Declination −40° 49′ 27.7034″[1]
Apparent magnitude (V) 5.49[2]
Characteristics
Evolutionary stage main sequence
Spectral type F4 V[3]
U−B color index −0.05[2]
B−V color index +0.47[2]
Astrometry
Radial velocity (Rv)+15.15±0.29[1] km/s
Proper motion (μ) RA: +126.920[1] mas/yr
Dec.: −122.577[1] mas/yr
Parallax (π)29.3153 ± 0.1115 mas[1]
Distance111.3 ± 0.4 ly
(34.1 ± 0.1 pc)
Absolute magnitude (MV)2.82[4]
Details[5]
Mass1.45+0.02
−0.01
 M
Radius1.87+0.07
−0.04
[1] R
Luminosity5.84±0.03[1] L
Surface gravity (log g)4.06±0.02 cgs
Temperature6,606±63 K
Metallicity [Fe/H]0.00±0.05 dex
Rotational velocity (v sin i)19.9±1.0[4] km/s
Age2.12+0.22
−0.16
 Gyr
Other designations
φ Gru, CD−41°15211, GJ 4330, HD 219693, HIP 115054, HR 8859, SAO 231539[6]
Database references
SIMBADdata

This object is an F-type main-sequence star with a stellar classification of F4 V,[3] where the luminosity class of 'V' indicates it is currently generating energy through hydrogen fusion at its core. It is 2.12[5] billion years old and is spinning with a projected rotational velocity of 20 km/s.[4] The star has 1.45[5] times the mass of the Sun and 1.87[1] times the Sun's radius. It is radiating 5.8[1] times as much luminosity as the Sun from its photosphere at an effective temperature of 6,606 km/s.[5]

References

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  1. ^ a b c d e f g h i j k 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 Przybylski, A.; Kennedy, P. M. (1965), "Radial velocities and three-colour photometry of 166 southern stars", Monthly Notices of the Royal Astronomical Society, 131: 95–104, Bibcode:1965MNRAS.131...95P, doi:10.1093/mnras/131.1.95.
  3. ^ a b Gray, R. O.; et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
  4. ^ a b c 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.
  5. ^ a b c d Aguilera-Gómez, Claudia; Ramírez, Iván; Chanamé, Julio (June 2018), "Lithium abundance patterns of late-F stars: an in-depth analysis of the lithium desert", Astronomy & Astrophysics, 614: 15, arXiv:1803.05922, Bibcode:2018A&A...614A..55A, doi:10.1051/0004-6361/201732209, S2CID 62799777, A55.
  6. ^ "phi Gru -- Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2017-06-19.
  7. ^ 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.
  8. ^ 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.