78 Ursae Majoris (78 UMa) is a binary star in the constellation Ursa Major. Its combined apparent magnitude is 4.93.[2] Parallax estimates by Hipparcos put it at 83 light-years, or 25.4 parsecs, away.[1]

78 Ursae Majoris
Observation data
Epoch J2000      Equinox J2000
Constellation Ursa Major
Right ascension  13h 00m 43.69949s[1]
Declination +56° 21′ 58.8102″[1]
Apparent magnitude (V) 4.93[2] (5.02 / 7.88)[3]
Characteristics
Evolutionary stage F2V[4]
U−B color index +0.00[5]
B−V color index +0.34[5]
Astrometry
Radial velocity (Rv)−9.8±0.9[6] km/s
Proper motion (μ) RA: 107.94[1] mas/yr
Dec.: 2.05[1] mas/yr
Parallax (π)39.30 ± 0.38[1] mas
Distance83.0 ± 0.8 ly
(25.4 ± 0.2 pc)
Absolute magnitude (MV)+2.84[7]
Orbit[8]
Period (P)104.9±0.6 yr
Semi-major axis (a)1.208±0.010
Eccentricity (e)0.388±0.009
Inclination (i)46.9±0.9°
Longitude of the node (Ω)88.0±1.1°
Periastron epoch (T)B 1921.224±0.403
Argument of periastron (ω)
(secondary)
119.2±1.5°
Other designations
BD+57° 1408, HD 113139, HIP 63503, HR 4931, SAO 28601[2]
Database references
SIMBADThe system
A
B

ReferencesEdit

  1. ^ a b c d e f van Leeuwen, F.; et al. (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.
  2. ^ a b c "* 78 UMa". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 19 August 2017.
  3. ^ Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (2002). "The Tycho double star catalogue". Astronomy and Astrophysics. 384: 180–189. Bibcode:2002A&A...384..180F. doi:10.1051/0004-6361:20011822.
  4. ^ Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Robinson, P. E. (2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I". The Astronomical Journal. 126 (4): 2048. arXiv:astro-ph/0308182. Bibcode:2003AJ....126.2048G. doi:10.1086/378365.
  5. ^ a b Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Bibcode:1986EgUBV........0M.
  6. ^ Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Bibcode:1953GCRV..C......0W.
  7. ^ Eggen, Olin J. (August 1998), "The Sirius Supercluster and Missing Mass near the Sun", The Astronomical Journal, 116 (2): 782–788, Bibcode:1998AJ....116..782E, doi:10.1086/300465.
  8. ^ "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Retrieved 19 August 2017.