WR 140

WR 140

This July 2022 image by the James Webb Space Telescope's Mid-Infrared Instrument shows WR 140 and its nebula.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cygnus
Right ascension 20h 20m 27.97608s
Declination +43° 51′ 16.2802″
Apparent magnitude (V) 6.85
Characteristics
Spectral type WC7pd + O5.5fc
Apparent magnitude (J) 5.547
Apparent magnitude (K) 5.037
U−B color index −0.35
B−V color index +0.40
Variable type WR
Astrometry
Radial velocity (Rv)3.10 km/s
Proper motion (μ) RA: −4.275±0.027 mas/yr
Dec.: −1.874±0.026 mas/yr
Parallax (π)0.5378±0.0237 mas
Distance1,518±21 pc
Absolute magnitude (MV)WR: −6.6 to −4.8
O: −6.11 to −5.94
Orbit
PrimaryO
NameWR
Period (P)2,895.00±0.29 d
Semi-major axis (a)0.008922±0.000067"
(13.55±0.21 au)
Eccentricity (e)0.8993±0.0013
Inclination (i)119.07±0.88°
Longitude of the node (Ω)353.87±0.67°
Periastron epoch (T)MJD 60,636.23±0.53
Argument of periastron (ω)
(secondary)
227.44±0.52°
Semi-amplitude (K1)
(primary)
26.50±0.48 km/s
Semi-amplitude (K2)
(secondary)
−75.25±0.63 km/s
Details
WR
Mass10.31±0.45 M
Luminosity537,000 L
Temperature70,000 K
O
Mass29.27±1.14 M
Radius35 R
Luminosity1.6 million L
Temperature35,000 K
Other designations
V1687 Cygni, BD+43°3571, HD 193793, HIP 100287, TYC 3164-1678-1, SBC9 1232, WDS J20205+4351, 2MASS J20202798+4351164
Database references
SIMBADdata

WR 140 is a spectroscopic binary containing an O-type star and a Wolf–Rayet star. It is located in the constellation of Cygnus, lying in the sky at the centre of the triangle formed by Deneb, γ Cygni and δ Cygni.