Omega2 Cygni, Latinized from ω2 Cygni, is the Bayer designation for a solitary[7] star in the northern constellation of Cygnus. It has an apparent visual magnitude of 5.5,[2] which is faintly visible to the naked eye on a dark night. Based upon an annual parallax shift of 8.17 mas,[1] it is located roughly 399 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.08 due to interstellar dust.[2]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Cygnus |
Right ascension | 20h 31m 18.81663s[1] |
Declination | +49° 13′ 13.0656″[1] |
Apparent magnitude (V) | 5.5292±0.0013[2] |
Characteristics | |
Spectral type | M2 III[3] |
Astrometry | |
Radial velocity (Rv) | −64.15±0.20[2] km/s |
Proper motion (μ) | RA: +9.21[1] mas/yr Dec.: −31.88[1] mas/yr |
Parallax (π) | 8.17 ± 0.19 mas[1] |
Distance | 399 ± 9 ly (122 ± 3 pc) |
Absolute magnitude (MV) | +0.00[4] |
Details | |
Luminosity | 301[5] L☉ |
Temperature | 3,847[5] K |
Other designations | |
Database references | |
SIMBAD | data |
This is a red giant star on the asymptotic giant branch, with a stellar classification of M2 III.[3] It is a suspected variable star, although the evidence is considered "doubtful or erroneous". If it does exist, the variability is small with an amplitude of 0.05 magnitude and a timescale of around 30 days.[8] There is a 58.3% chance that this star is a member of the Hercules stream.[2]
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: CS1 maint: postscript (link)