Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cygnus |
Right ascension | 19h 36m 49.35633s [1] |
Declination | +50° 11′ 59.7198″ [1] |
Apparent magnitude (V) | 6.1 - 14.4 [2] |
Characteristics | |
Spectral type | S2.5,9e-S6,9e(Tc) [3] |
Variable type | Mira [2] |
Astrometry | |
Proper motion (μ) |
RA: −3.158
[1]
mas/
yr Dec.: −5.755 [1] mas/ yr |
Parallax (π) | 1.4835 ± 0.0963 mas [1] |
Distance | 2,200 ± 100
ly (670 ± 40 pc) |
Details | |
Mass | 0.85 [4] M☉ |
Luminosity | 11,700 [5] L☉ |
Surface gravity (log g) | −0.50 [4] cgs |
Temperature | 2,538 [4] K |
Metallicity [Fe/H] | +0.50 [4] dex |
Other designations | |
Database references | |
SIMBAD | data |
R Cygni is a variable star of the Mira type in the constellation Cygnus, less than 4' from θ Cygni. This is a red giant star on the asymptotic giant branch located around 2,200 light years away. It is an S-type star ranging between spectral types S2.5,9e to S6,9e(Tc). [3]
Stars at this mass range and evolutionary stage are pulsationally unstable, displaying a variation in their light output. [7] R Cygni has a maximum magnitude of 6.1 and a minimum magnitude of 14.4, with a period of 426.45 days. [2] The variation of this star was discovered by English astronomer N. R. Pogson in 1852, and it has a history of recorded brightness measurements stretching back more than a century. [7] R Cygni shows distinct period-doubling, where alternate maxima are of different brightness, hence the real period of pulsation could be considered to be twice that from one maximum to the next. [8]
The Catalog of Components of Double and Multiple Stars lists 10th magnitude BD+49 3065 as a companion to R Cygni, at a separation of 91", and both stars lie at approximately the same distance. The Washington Double Star Catalog additionally lists a 15th magnitude star as a companion at a separation of about 14". [9]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cygnus |
Right ascension | 19h 36m 49.35633s [1] |
Declination | +50° 11′ 59.7198″ [1] |
Apparent magnitude (V) | 6.1 - 14.4 [2] |
Characteristics | |
Spectral type | S2.5,9e-S6,9e(Tc) [3] |
Variable type | Mira [2] |
Astrometry | |
Proper motion (μ) |
RA: −3.158
[1]
mas/
yr Dec.: −5.755 [1] mas/ yr |
Parallax (π) | 1.4835 ± 0.0963 mas [1] |
Distance | 2,200 ± 100
ly (670 ± 40 pc) |
Details | |
Mass | 0.85 [4] M☉ |
Luminosity | 11,700 [5] L☉ |
Surface gravity (log g) | −0.50 [4] cgs |
Temperature | 2,538 [4] K |
Metallicity [Fe/H] | +0.50 [4] dex |
Other designations | |
Database references | |
SIMBAD | data |
R Cygni is a variable star of the Mira type in the constellation Cygnus, less than 4' from θ Cygni. This is a red giant star on the asymptotic giant branch located around 2,200 light years away. It is an S-type star ranging between spectral types S2.5,9e to S6,9e(Tc). [3]
Stars at this mass range and evolutionary stage are pulsationally unstable, displaying a variation in their light output. [7] R Cygni has a maximum magnitude of 6.1 and a minimum magnitude of 14.4, with a period of 426.45 days. [2] The variation of this star was discovered by English astronomer N. R. Pogson in 1852, and it has a history of recorded brightness measurements stretching back more than a century. [7] R Cygni shows distinct period-doubling, where alternate maxima are of different brightness, hence the real period of pulsation could be considered to be twice that from one maximum to the next. [8]
The Catalog of Components of Double and Multiple Stars lists 10th magnitude BD+49 3065 as a companion to R Cygni, at a separation of 91", and both stars lie at approximately the same distance. The Washington Double Star Catalog additionally lists a 15th magnitude star as a companion at a separation of about 14". [9]