Omega Leonis

ω Leonis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Leo
Right ascension 09h 28m 27.39861s[1]
Declination +09° 03′ 24.4255″[1]
Apparent magnitude (V) 5.42[2] (5.69 + 7.28)[3]
Characteristics
ω Leo A
Evolutionary stage main sequence[4]
Spectral type G1 V[5]
U−B color index +0.12[2]
B−V color index +0.60[2]
Astrometry
Radial velocity (Rv)−7.6±0.2[6] km/s
Proper motion (μ) RA: +36.98[1] mas/yr
Dec.: +5.78[1] mas/yr
Parallax (π)30.15 ± 1.45 mas[1]
Distance108 ± 5 ly
(33 ± 2 pc)
Absolute magnitude (MV)+2.72[7]
Orbit[8]
Period (P)42,678.5 days
Eccentricity (e)0.56
Periastron epoch (T)2436769.0 (JD)
Argument of periastron (ω)
(secondary)		124.6°
Semi-amplitude (K1)
(primary)		2.2 km/s
Details
ω Leo A
Mass1.35+0.05
−0.03[9] M☉
Luminosity6[10] L☉
Surface gravity (log g)3.82±0.05[9] cgs
Temperature5940±85[9] K
Metallicity [Fe/H]0.02±0.06[9] dex
Rotational velocity (v sin i)5.1[4] km/s
Age3.68+0.31
−0.28[9] Gyr
Other designations
ω Leo, 2 Leo, BD+09°2188, HD 81858, HIP 46454, HR 3754, SAO 117717[11]
Database references
SIMBADdata

ω Leonis (Latinised as Omega Leonis, abbreviated to ω Leo or Omega Leo), is a star system located in the zodiac constellation of Leo. It is visible to the naked eye in the absence of light pollution, with an apparent visual magnitude of about 5.4. The distance to this star, as determined using parallax measurements, is around 108 light years from the Sun. Because of its location close to the ecliptic, it is subject to being obscured by the Moon, and potentially by planets.

This is a spectroscopic binary star system with an orbital period of 116.8 years and an eccentricity of 0.56.[8] In 2010, speckle interferometry observations showed an angular separation of 738±10 mas between the two components along a position angle of 102.7°±0.6°.[12] The primary is a G-type main sequence star with a spectral classification of G1 V.[5] It has about 35%[9] more mass than the Sun and shines six[10] times as brightly from an outer atmosphere that has an effective temperature of 5940 K.[9] The system is roughly 3.7 billion years old[9] and is a member of the galactic thin disk population.[9]

  1. ^ a b c d e Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Mermilliod1986 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Malkov2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Schroeder2009 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Abt2009 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Pourbaix2004 was invoked but never defined (see the help page).
  9. ^ a b c d e f g h i Cite error: The named reference Ramirez2012 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Mcdonald2012 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 prieur2012 was invoked but never defined (see the help page).