HD 115004 is a single[7] star in the northern constellation of Canes Venatici. It is faintly visible to the naked eye with an apparent visual magnitude of 4.94.[2] Based upon an annual parallax shift of 7.10±0.24 mas,[1] it is located around 460 light years from the Sun. The star is moving closer with a heliocentric radial velocity of −22 km/s.[2] HD 115004 will make its closest approach in about 1.7 million years at a separation of around 390 ly (119.45 pc).[2]

HD 115004
Observation data
Epoch J2000      Equinox J2000
Constellation Canes Venatici
Right ascension 13h 13m 42.94245s[1]
Declination +40° 09′ 10.3802″[1]
Apparent magnitude (V) 4.94[2]
Characteristics
Spectral type G8.5 III CN0.5[3]
B−V color index 1.061±0.002[2]
Astrometry
Radial velocity (Rv)−22.10±0.14[2] km/s
Proper motion (μ) RA: −51.21[1] mas/yr
Dec.: +14.75[1] mas/yr
Parallax (π)7.10 ± 0.24 mas[1]
Distance460 ± 20 ly
(141 ± 5 pc)
Absolute magnitude (MV)−0.80[2]
Details[4]
Mass3.17±0.26 M
Radius22.89±0.85 R
Luminosity241.7±17.3 L
Surface gravity (log g)2.23±0.05 cgs
Temperature4,761±24 K
Metallicity [Fe/H]−0.10±0.10 dex
Rotational velocity (v sin i)5.8[5] km/s
Age440±130 Myr
Other designations
BD+40° 2633, HD 115004, HIP 64540, HR 4997, SAO 44519[6]
Database references
SIMBADdata

This is an evolved giant star, most likely (97% chance) on the horizontal branch,[4] with a stellar classification of G8.5 III CN0.5.[3] The suffix notation indicates a mild overabundance of the CN molecule in the stellar atmosphere. It has an estimated 3.2 times the mass of the Sun and, at the age of 440 million years, has expanded to 23 times the Sun's radius. The star is radiating around 242 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,761 K.[4]

References

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  1. ^ a b c d e f 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.
  2. ^ a b c d e f g 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 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
  4. ^ a b c Reffert, Sabine; et al. (2015), "Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity", Astronomy & Astrophysics, 574: A116, arXiv:1412.4634, Bibcode:2015A&A...574A.116R, doi:10.1051/0004-6361/201322360, hdl:10722/215277, S2CID 59334290.
  5. ^ De Medeiros, J. R.; et al. (November 2000), "Rotation and lithium in single giant stars", Astronomy and Astrophysics, 363: 239–243, arXiv:astro-ph/0010273, Bibcode:2000A&A...363..239D.
  6. ^ "HD 115004". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-06-07.
  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.