Tau Cygni

Starbox begin
name=GJ 822.1 A / GJ 822.1 B cite web
title=Simbad Query Result | work=Simbad
url=http://simbad.u-strasbg.fr/simbad/sim-id?Ident=CCDM%20J21148%2B3803AB
accessdate=October 18
accessyear=2007] cite web
title=Simbad Query Result | work=Simbad
url=http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=CCDM+J21148%2B3803A&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
accessdate=October 18
accessyear=2007] cite web
title=Simbad Query Result | work=Simbad
url=http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=CCDM+J21148%2B3803B&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id
accessdate=October 18
accessyear=2007] Starbox observe
epoch=J2000.0
constell=Cygnus
ra=21h 14m 47.4916s
dec=+38° 2' 43.141"
appmag_v=3.84 / 6.44|Starbox character
class=F2IV / G0V
b-v=+0.38 / +0.60
u-b=+0.03 / +0.09 |Starbox astrometry
radial_v=-21.1
prop_mo_ra=195.75
prop_mo_dec=410.03
parallax=47.80
p_error=0.61 |Starbox catalog
names=Tau Cygni, 65 Cygni, HR 8130, BD+37°4240, HD 202444, SAO 71121, HIP 104887, GC 29723, CCDM J21148+3803AB

Tau Cygni (τ Cyg) is a binary star system in the constellation Cygnus, approximately 69 light years away from Earth. The main star, 4th magnitude GJ 822.1 A, is a yellowish white subgiant star of the spectral type F2IV. It therefore has a surface temperature of 6,000 to 7,500 kelvins and is larger, hotter, and several times as bright as our Sun. Its companion, 6th magnitude GJ 822.1 B, is a yellow main sequence star of the spectral type G0V. It is similar to our Sun in size, surface temperature, and luminosity.

References