83 Ursae Majoris

83 Ursae Majoris

A light curve for IQ Ursae Majoris, plotted from Hipparcos data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Ursa Major
Right ascension 13h 40m 44.27274s[2]
Declination +54° 40′ 53.8860″[2]
Apparent magnitude (V) 4.69 - 4.75[3]
Characteristics
Spectral type M2 III[4]
B−V color index +1.630±0.006[5]
Variable type SRb[3]
Astrometry
Radial velocity (Rv)−18.61±0.20[6] km/s
Proper motion (μ) RA: −19.418 mas/yr[2]
Dec.: −10.63 mas/yr[2]
Parallax (π)5.5963 ± 0.1399 mas[2]
Distance580 ± 10 ly
(179 ± 4 pc)
Absolute magnitude (MV)−1.39[5]
Details
Mass1.1[7] M☉
Radius83.3±3.1[8] R☉
Luminosity1,250[9] L☉
Surface gravity (log g)1.06±0.16[10] cgs
Temperature3,705±16[10] K
Metallicity [Fe/H]−0.1±0.08[10] dex
Other designations
83 UMa, IQ UMa, BD+55°1625, HD 119228, HIP 66738, HR 5154, SAO 28843[11]
Database references
SIMBADdata

83 Ursae Majoris is a candidate binary star[12] system in the northern circumpolar constellation of Ursa Major. It is a semiregular variable star, and it has been given the variable star designation IQ Ursae Majoris. It ranges in brightness from apparent visual magnitude 4.69 to 4.75.[3] Percy and Au (1994) identified it as a small amplitude red variable with an irregular behavior, having a characteristic time scale of 20 days.[13] Based upon an annual parallax shift of 5.60 mas,[2] it is located roughly 580 light years from the Sun. The system is moving closer with a heliocentric radial velocity of −18.6[6] km/s.

The visible component is an evolved red giant with a stellar classification of M2 III.[4] It is a marginal barium star, showing an enhanced abundance of s-process elements in its outer atmosphere. This material may have been acquired during a previous mass transfer from a now white dwarf companion, or self-enriched by a dredge-up during the asymptotic giant branch process.[14]

  1. ^ Cite error: The named reference HipDataAccess was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference DR3 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Keenan1989 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference DeBruijne2012 was invoked but never defined (see the help page).
  7. ^ Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; de Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (August 2019), "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18", Astronomy & Astrophysics, 628: A94, arXiv:1904.11302, Bibcode:2019A&A...628A..94A, doi:10.1051/0004-6361/201935765, ISSN 0004-6361.
  8. ^ Cite error: The named reference Baines2023 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference chandler2016 was invoked but never defined (see the help page).
  10. ^ a b c Cite error: The named reference MILES was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Percy1994 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference gomez1997 was invoked but never defined (see the help page).