HD 91324 is a likely binary[4] star system in the southern constellation of Vela. It is visible to the naked eye with an apparent visual magnitude of 4.89.[2] The distance to HD 91324, as determined from its annual parallax shift of 45.6 mas,[1] is 71.5 light years. It is moving further from the Earth with a heliocentric radial velocity of +21 km/s.[1]

HD 91324
Observation data
Epoch J2000      Equinox J2000
Constellation Vela
Right ascension 10h 31m 21.82130s[1]
Declination −53° 42′ 55.7373″[1]
Apparent magnitude (V) 4.89[2]
Characteristics
Spectral type F9V Fe-0.8 CH-0.7[3]
B−V color index 0.500±0.015[2]
Astrometry
Radial velocity (Rv)+21.37±0.20[1] km/s
Proper motion (μ) RA: −420.131[1] mas/yr
Dec.: +209.450[1] mas/yr
Parallax (π)45.6124 ± 0.1682 mas[1]
Distance71.5 ± 0.3 ly
(21.92 ± 0.08 pc)
Absolute magnitude (MV)3.20[2]
Details[4]
HD 91324 A
Mass1.18 M
Radius1.86±0.06 R
Luminosity4.55[2] L
Surface gravity (log g)3.97±0.10 cgs
Temperature6,127±70 K
Metallicity [Fe/H]−0.27±0.06 dex
Rotational velocity (v sin i)8.8±0.6 km/s
Age3.52±1.08[5] Gyr
Other designations
CD−53° 3569, GJ 397.2/9332, HD 91324, HIP 51523, HR 4134, SAO 238146[6]
Database references
SIMBADdata

The primary, component A, is a metal-deficient[7] F-type main-sequence star with a stellar classification of F9V Fe-0.8 CH-0.7,[3] where the suffix notation indicates underabundances of iron and methine in its spectrum. It is around 3.5[5] billion years old and is spinning with a projected rotational velocity of 9 km/s. The star has 1.18 times the mass of the Sun and 1.86 times the Sun's radius.[4] It is radiating 4.55[2] times the Sun's luminosity from its photosphere at an effective temperature of 6,127 K.[4]

A faint star designated 2MASS J10313234–5338010[8] was found to be a possible companion to HD 91324 through a proper motion study combining data from the Two Micron All-Sky Survey and the WISE space telescope. The projected separation of the two components is 309, or 6,700 AU. Proper motion measurements for the two stars are almost identical making HD 91324 a likely binary star system. The photometry of 2MASS J10313234–5338010 is consistent with it being a red dwarf of spectral type M5 or M6.[9]

References

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  1. ^ a b c d e f g h 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 e f 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, S2CID 119257644.
  3. ^ a b Gray, R. O.; et al. (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 d Fuhrmann, K.; et al. (February 2017), "Multiplicity among Solar-type Stars", The Astrophysical Journal, 836 (1): 23, Bibcode:2017ApJ...836..139F, doi:10.3847/1538-4357/836/1/139, 139.
  5. ^ a b Pace, G. (March 2013), "Chromospheric activity as age indicator. An L-shaped chromospheric-activity versus age diagram", Astronomy & Astrophysics, 551: 4, arXiv:1301.5651, Bibcode:2013A&A...551L...8P, doi:10.1051/0004-6361/201220364, S2CID 56420519, L8.
  6. ^ "HD 91324". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-08-13.
  7. ^ da Silva, L. (July 1975), "The study of HR 3018, HD 91324 and alpha Crv and its implication for the age-abundance correlation of the neighbour stars", Astronomy and Astrophysics, 41: 287–300, Bibcode:1975A&A....41..287D.
  8. ^ "2MASS J10313234-5338010". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-08-13.
  9. ^ Luhman, Kevin L.; et al. (2012), "New M, L, and T Dwarf Companions to Nearby Stars from the Wide-field Infrared Survey Explorer", The Astrophysical Journal, 760 (2), 152, arXiv:1211.3977, Bibcode:2012ApJ...760..152L, doi:10.1088/0004-637X/760/2/152, S2CID 51010785.