5 Ursae Minoris

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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[1] mas
Distance 359 ± 5 ly
(110 ± 2 pc)
Absolute magnitude (MV) −0.96[4]
Details
Mass 1.86[2] M
Radius 16[5] R
Luminosity 447[2] L
Surface gravity (log g) 1.91[6] cgs
Temperature 4,095±39[2] K
Metallicity [Fe/H] −0.16[6] dex
Rotational velocity (v sin i) 1.9[7] km/s
Age 2.00[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 light years. 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[edit]

  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:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  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:1507.01466Freely accessible, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88. 
  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:1108.4971Freely accessible, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015. 
  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/0012289Freely accessible, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451. 
  6. ^ a b Soubiran, C.; et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics, 515: A111, arXiv:1004.1069Freely accessible, Bibcode:2010A&A...515A.111S, doi:10.1051/0004-6361/201014247. 
  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/0010273Freely accessible, 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