OU Geminorum

OU Geminorum

A visual band light curve for OU Geminorum, adapted from Bopp et al. (1981)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Gemini
Right ascension 06h 26m 10.2464s[2]
Declination +18° 45′ 24.896″[2]
Apparent magnitude (V) 6.768[3]
Characteristics
Spectral type K3Vk[3]
U−B color index 0.662[3]
B−V color index 0.972[3]
Variable type BY Dra[4]
Astrometry
Radial velocity (Rv)−8.98±0.10[5] km/s
Proper motion (μ) RA: −124.020±0.097[2] mas/yr
Dec.: −159.335±0.054[2] mas/yr
Parallax (π)68.46 ± 0.34 mas[2]
Distance47.6 ± 0.2 ly
(14.61 ± 0.07 pc)
Absolute magnitude (MV)5.93±0.05[3]
Orbit[5]
PrimaryOU Gem Aa
CompanionOU Gem Ab
Period (P)6.991878±0.000004 d
Eccentricity (e)0.151±0.0024
Periastron epoch (T)54900.0719±0.0203 JD
Argument of periastron (ω)
(secondary)		77.63±1.09°
Semi-amplitude (K1)
(primary)		57.09±0.15 km/s
Semi-amplitude (K2)
(secondary)		66.22±0.28 km/s
Details[6]
OU Gem Aa
Mass0.85 M☉
Radius0.81 R☉
Surface gravity (log g)4.55 cgs
Temperature4960 K
OU Gem Ab
Mass0.71 M☉
Radius0.65 R☉
Surface gravity (log g)4.65 cgs
Temperature4390 K
Other designations
OU Gem, BD+18 1214, GJ 233, HD 45088, HIP 30630, SAO 95677[7]
Database references
SIMBADdata

OU Geminorum (OU Gem) is a visual binary or possible triple star located in the constellation of Gemini.

The system has an absolute magnitude of 5.93, so at a distance of 48 light years it has an apparent magnitude of 6.77 when viewed from earth. It also has a total proper motion of 0.210"/yr and belongs to the Ursa Major stream.

The system is a much studied BY Draconis variable star with a period of 6.99 days.[4] The primary star has a spectral type of K3Vk. The secondary star in the system has a surface temperature of 4486±50 K and orbits the primary in about seven days.[8][9]

  1. ^ Cite error: The named reference Bopp1981 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Gaia2016 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference mnras403_4_1949 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Bopp1980 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Glazunova2014 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Fuhrmann was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference cns was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference cern was invoked but never defined (see the help page).