Astronomy:HR 5256

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Short description: Star in the constellation Ursa Major
HR 5256
Observation data
Equinox J2000.0]] (ICRS)
Constellation Ursa Major
Right ascension  13h 57m 32.0592s[1]
Declination +61° 29′ 34.2994″[1]
Apparent magnitude (V) 6.52[2][3]
Characteristics
Spectral type K3 V[4]
U−B color index 0.98[5]
B−V color index 1.01[5]
Astrometry
Radial velocity (Rv)−26.376±0.0011[1] km/s
Proper motion (μ) RA: −32.074±0.063[1] mas/yr
Dec.: 216.317±0.049[1] mas/yr
Parallax (π)99.2285 ± 0.0232[1] mas
Distance32.869 ± 0.008 ly
(10.078 ± 0.002 pc)
Absolute magnitude (MV)6.51[3]
Details[3]
Mass0.82 M
Radius0.78[6] R
Luminosity0.28 L
Surface gravity (log g)4.57 cgs
Temperature4,811 K
Metallicity [Fe/H]0.17[7] dex
Rotational velocity (v sin i)4.6 km/s
Age5.36 Gyr
Other designations
BD+62°1325, HD 122064, HIP 68184, HR 5356, SAO 16230, G 239-008, LTT 14084[8]
Database references
SIMBADdata

HR 5256 is a star located thirty-three[1] light-years away from the Sun in the northern circumpolar constellation of Ursa Major. It has an orange hue and is a challenge to view with the naked eye, having an apparent visual magnitude of 6.52[2] The distance to this star is very nearly 10 parsecs, so the absolute magnitude of 6.51[3] is nearly the same as the star's apparent magnitude. HR 5256 is drifting nearer to the Sun with a radial velocity of −26.4 km/s,[1] and will make its closest approach to the Sun in about 333,000±16,000 years, when it will be at a distance of 12.72 ± 0.65 light-years.[9]

This object is an ordinary K-type main-sequence star with a stellar classification of K3 V,[4] which indicates it is undergoing core hydrogen fusion. It is over five billion years of age and is spinning slowly with a projected rotational velocity of 4.6 km/s.[3] The star has an estimated 82%[3] of the Sun's mass and 78% of the Sun's radius.[6] It is radiating just 28% of the luminosity of the Sun from its photosphere at an effective temperature of 4,811 K.[3]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 Oja, T. (August 1991). "UBV photometry of stars whose positions are accurately known. VI". Astronomy and Astrophysics Supplement Series 89 (2): 415–419. Bibcode1991A&AS...89..415O. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Luck, R. Earle (January 2017). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal 153 (1): 19. doi:10.3847/1538-3881/153/1/21. 21. Bibcode2017AJ....153...21L. 
  4. 4.0 4.1 Marrese, P. M.; Boschi, F.; Munari, U. (August 2003). "High resolution spectroscopy over lambda lambda 8500-8750 Å for GAIA. IV. Extending the cool MK stars sample". Astronomy and Astrophysics 406: 995–999. doi:10.1051/0004-6361:20030647. Bibcode2003A&A...406..995M. 
  5. 5.0 5.1 "ARICNS 4C04262". ARICNS. Astronomisches Rechen-Institut Heidelberg. March 4, 1998. http://www.ari.uni-heidelberg.de/datenbanken/aricns/cnspages/4c04262.htm. 
  6. 6.0 6.1 Takeda, Genya (February 2007). "Structure and Evolution of Nearby Stars with Planets. II. Physical Properties of ~1000 Cool Stars from the SPOCS Catalog". The Astrophysical Journal Supplement Series 168 (2): 297–318. doi:10.1086/509763. Bibcode2007ApJS..168..297T.  Data obtained from a VizieR query.
  7. Soubiran, C.; Bienaymé, O.; Mishenina, T. V.; Kovtyukh, V. V. (March 2008). "Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants". Astronomy and Astrophysics 480 (1): 91–101. doi:10.1051/0004-6361:20078788. Bibcode2008A&A...480...91S. 
  8. "HD 122064". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+122064. 
  9. Bailer-Jones, C.A.L. et al. (2018). "New stellar encounters discovered in the second Gaia data release". Astronomy & Astrophysics 616: A37. doi:10.1051/0004-6361/201833456. Bibcode2018A&A...616A..37B.