Theta Cygni
star system in the constellation Cygnus
Theta Cygni is a binary star system in the northern constellation of Cygnus. Its name is a Bayer designation, which is Latinized from θ Cygni and abbreviated θ Cyg or θ Cyg. The combined apparent visual magnitude of this system is 4.5, so it can be seen as a point of light with the naked eye in sufficiently dark skies. Based upon parallax measurements, it is located at a distance of about 60.1 light-years (18.4 pc) from the Earth. It is suspected of hosting an extrasolar planet.
Properties
The spectrum of the primary star matches a stellar classification of F3 V. The luminosity class 'V' is associated with a category of stars called main sequence, which, like the Sun, are generating energy through the nuclear fusion of hydrogen at their cores. The outer envelope of this star is radiating 4.2 times the luminosity of the Sun at an effective temperature of about 6,381 K, which gives it the yellow-white hue typical of F-type stars. Theta Cygni is larger than the Sun, with about 38% more mass and a 58% greater radius. The estimated age of this star is probably in the range of 0.6–1.9 billion years.
Companions
θ Cygni has several faint companions.
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This entry incorporates text from “Theta Cygni” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.