5 Ursae Minoris

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]

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]
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

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. 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. 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. 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. Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
6. 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.