Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cygnus |
Right ascension | 21h 36m 02.49619s [1] |
Declination | +44° 22′ 28.5292″ [1] |
Apparent magnitude (V) | 5.10 - 6.83 [2] |
Characteristics | |
Spectral type | M4e-M6e(Tc:)III [3] |
U−B color index | +1.24 [4] |
B−V color index | +1.59 [4] |
Variable type | SRb [5] |
Astrometry | |
Radial velocity (Rv) | −12.87 [6] km/s |
Proper motion (μ) |
RA: 65.17 ± 0.42
[1]
mas/
yr Dec.: 1.74 ± 0.30 [1] mas/ yr |
Parallax (π) | 5.72 ± 0.38 mas [1] |
Distance | 570 ± 40
ly (170 ± 10 pc) |
Absolute magnitude (MV) | −0.43 [7] |
Details | |
Mass | 0.98 [8] M☉ |
Radius | 227 [8] R☉ |
Luminosity | 5,888 [8] L☉ |
Temperature | 3,373 [8] K |
Other designations | |
Database references | |
SIMBAD | data |
W Cygni is a semi-regular variable star in the constellation Cygnus, located 570 light-years from Earth. It lies less than half a degree southeast of ρ Cygni. W Cygni is, at times, a naked-eye star but it was not given a Bayer or Flamsteed designation. It has been proposed as a binary star system with a hotter main sequence companion, but this has not been confirmed. [9]
W Cygni was discovered to be variable by John Ellard Gore, and first published in 1885. [10] It has a maximum magnitude of 5.10 and a minimum magnitude 6.83. The star is catalogued as having a primary period of 131.7 days, but shows variations with a variety of periods around 131 days as well as 234 days. [11] [10] It is believed to be pulsating in the first overtone. [8] There is some evidence of additional very slow and small variations in the light curve on a time scale of 3,000–5,000 days. [12]
This star is an aging red giant on the asymptotic giant branch (AGB). Its spectral type ranges between M4e and M6e, and it shows possible elevated levels of Technetium. [2] The masses of AGB stars are poorly known, but using the pulsation properties of W Cygni, it mass is calculated to be slightly less than the sun's. [8] It has expanded to 227 times the girth of the Sun and is radiating 5,888 times the Sun's luminosity from its swollen photosphere at an effective temperature of 3,373 K. [8]
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cygnus |
Right ascension | 21h 36m 02.49619s [1] |
Declination | +44° 22′ 28.5292″ [1] |
Apparent magnitude (V) | 5.10 - 6.83 [2] |
Characteristics | |
Spectral type | M4e-M6e(Tc:)III [3] |
U−B color index | +1.24 [4] |
B−V color index | +1.59 [4] |
Variable type | SRb [5] |
Astrometry | |
Radial velocity (Rv) | −12.87 [6] km/s |
Proper motion (μ) |
RA: 65.17 ± 0.42
[1]
mas/
yr Dec.: 1.74 ± 0.30 [1] mas/ yr |
Parallax (π) | 5.72 ± 0.38 mas [1] |
Distance | 570 ± 40
ly (170 ± 10 pc) |
Absolute magnitude (MV) | −0.43 [7] |
Details | |
Mass | 0.98 [8] M☉ |
Radius | 227 [8] R☉ |
Luminosity | 5,888 [8] L☉ |
Temperature | 3,373 [8] K |
Other designations | |
Database references | |
SIMBAD | data |
W Cygni is a semi-regular variable star in the constellation Cygnus, located 570 light-years from Earth. It lies less than half a degree southeast of ρ Cygni. W Cygni is, at times, a naked-eye star but it was not given a Bayer or Flamsteed designation. It has been proposed as a binary star system with a hotter main sequence companion, but this has not been confirmed. [9]
W Cygni was discovered to be variable by John Ellard Gore, and first published in 1885. [10] It has a maximum magnitude of 5.10 and a minimum magnitude 6.83. The star is catalogued as having a primary period of 131.7 days, but shows variations with a variety of periods around 131 days as well as 234 days. [11] [10] It is believed to be pulsating in the first overtone. [8] There is some evidence of additional very slow and small variations in the light curve on a time scale of 3,000–5,000 days. [12]
This star is an aging red giant on the asymptotic giant branch (AGB). Its spectral type ranges between M4e and M6e, and it shows possible elevated levels of Technetium. [2] The masses of AGB stars are poorly known, but using the pulsation properties of W Cygni, it mass is calculated to be slightly less than the sun's. [8] It has expanded to 227 times the girth of the Sun and is radiating 5,888 times the Sun's luminosity from its swollen photosphere at an effective temperature of 3,373 K. [8]