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5 Ursae Minoris
Observation data
Epoch J2000       Equinox J2000
Constellation Ursa Minor
Right ascension 14h 27m 31.54335s [1]
Declination +75° 41′ 45.5717″ [1]
Apparent magnitude (V) 4.253 [2]
Characteristics
Spectral type K4-III [3]
B−V color index 1.457 [2]
Astrometry
Radial velocity (Rv)+9.34 [2] km/s
Proper motion (μ) RA: +8.79 [1]  mas/ yr
Dec.: +21.76 [1]  mas/ yr
Parallax (π)9.09 ± 0.13  mas [1]
Distance359 ± 5  ly
(110 ± 2  pc)
Absolute magnitude (MV)−0.96 [4]
Details
Mass1.86 [2]  M
Radius16 [5]  R
Luminosity447 [2]  L
Surface gravity (log g)1.91 [6]  cgs
Temperature4,095±39 [2]  K
Metallicity [Fe/H]−0.16 [6]  dex
Rotational velocity (v sin i)1.9 [7] km/s
Age2.00 [2]  Gyr
Other designations
5 UMi, NSV 6687, BD+76° 527, FK5 1379, HD 127700, HIP 70692, HR 5430, SAO 8024, WDS J14275+7542A [8]
Database references
SIMBAD data

5 Ursae Minoris is a star in the circumpolar constellation of Ursa Minor. It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.253. [2] The distance to this star, as determined from an annual parallax shift of 9.09±0.13  mas, [1] is about 110 pc. It is moving further away with a heliocentric radial velocity of +9 km/s. [2]

With an age of around two billion years, this is an evolved red giant with a stellar classification of K4-III; [3] a star that has used up its core hydrogen and has expanded. It is a mild barium star, which may indicate it is a binary with a white dwarf companion, [9] and is very lithium-weak. [10] The star has an estimated 1.86 [2] times the mass of the Sun and has expanded to about 16 [5] times the Sun's radius. It is radiating 447 [2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,095 K. [2]

References

  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 h i j k l Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv: 1507.01466, Bibcode: 2015AJ....150...88L, doi: 10.1088/0004-6256/150/3/88, S2CID  118505114.
  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. ^ 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.
  5. ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics (Third ed.), 367 (2): 521–524, arXiv: astro-ph/0012289, Bibcode: 2001A&A...367..521P, doi: 10.1051/0004-6361:20000451, S2CID  425754.
  6. ^ a b Soubiran, C.; et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics, 515: A111, arXiv: 1004.1069, Bibcode: 2010A&A...515A.111S, doi: 10.1051/0004-6361/201014247, S2CID  118362423.
  7. ^ 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.
  8. ^ "5 UMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-04-02.
  9. ^ McClure, R. D. (May 1, 1983), "The binary nature of the barium stars. II - Velocities, binary frequency, and preliminary orbits", Astrophysical Journal, Part 1, 268: 264–273, Bibcode: 1983ApJ...268..264M, doi: 10.1086/160951.
  10. ^ Brown, Jeffery A.; et al. (October 1989), "A search for lithium-rich giant stars", Astrophysical Journal Supplement Series, 71: 293–322, Bibcode: 1989ApJS...71..293B, doi: 10.1086/191375