Omega Geminorum
Star in the constellation Gemini
From Wikipedia, the free encyclopedia
Omega Geminorum, Latinized from ω Geminorum, is a star located in the middle of the northern zodiac constellation of Gemini. With an apparent visual magnitude of 5.18,[2] it is faintly visible to the naked eye. According to the Bortle scale, it can be viewed from dark suburban skies. With an annual parallax shift of just 2.19 mas,[1] it is located about 1,500 light years from the Sun.
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Gemini |
| Right ascension | 07h 02m 24.78033s[1] |
| Declination | +24° 12′ 55.6051″[1] |
| Apparent magnitude (V) | 5.18[2] |
| Characteristics | |
| Spectral type | G5 II[3] |
| U−B color index | +0.68[2] |
| B−V color index | +0.95[2] |
| Variable type | Cepheid?[4] |
| Astrometry | |
| Radial velocity (Rv) | −9.10±0.40[5] km/s |
| Proper motion (μ) | RA: −6.74[1] mas/yr Dec.: -0.25[1] mas/yr |
| Parallax (π) | 2.19±0.26 mas[1] |
| Distance | approx. 1,500 ly (approx. 460 pc) |
| Absolute magnitude (MV) | −3.06[6] |
| Details | |
| Mass | 6.3±0.5[3] M☉ |
| Radius | 72[7] R☉ |
| Luminosity | 1,813[8] L☉ |
| Surface gravity (log g) | 2.45[9] cgs |
| Temperature | 5,090[9] K |
| Metallicity [Fe/H] | −0.02[9] dex |
| Rotational velocity (v sin i) | 10[10] km/s |
| Age | 14.8[3] Myr |
| Other designations | |
| ω Gem, 42 Geminorum, BD+24°1502, FK5 1182, HD 52497, HIP 33927, HR 2630, SAO 78999.[11] | |
| Database references | |
| SIMBAD | data |
This is an evolved bright giant star with a stellar classification of G5 II.[3] It is positioned near the instability strip and in 1977 was listed as a candidate cepheid variable star[12] with a luminosity amplitude of 0.086 and a period of 0.7282 days.[4] The interferometer-measured angular diameter of this star is 1.47±0.21 mas.[13] At its estimated distance, this yields a physical size of about 72 times the radius of the Sun.[7] It has 6.3[3] times the mass of the Sun and radiates 1,813[8] times the solar luminosity from its outer atmosphere at an effective temperature of 5,090 K.[9]
