ξ Cygni (Latinised as Xi Cygni) is a
spectroscopic binary star in the
constellation Cygnus. Its apparent magnitude is 3.73 and it is located around away.
The system contains two stars which orbit every 18 years in a mildly eccentric orbit. The primary star is a
supergiant
Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8. The temperature range of supergiant stars spa ...
with a
spectral type
In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the ...
of around K4, while the secondary is an
A-type main-sequence star
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between ...
with a spectral type of A1.5. Stellar winds from the supergiant have been measured at around 50 km/s, but with variations in speed and individual line strengths.
[
ξ Cygni is in the ]Kepler
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws o ...
spacecraft's field of view but no planets have been detected.
References
{{Stars of Cygnus
Cygnus (constellation)
K-type supergiants
Spectroscopic binaries
Cygni, Xi
104060
8079
200905
A-type main-sequence stars
Cygni, 62
Durchmusterung objects