Deneb, << DEHN ehb, >> is the brightest star in the constellation Cygnus, or the Swan. Deneb is also called Alpha Cygni. It is one of the most brilliant stars visible to the unaided eye, having an apparent magnitude of 1.25 (see Magnitude ). Deneb appears faint because it is far away, but the star is actually very bright. Scientists aren’t sure of Deneb’s exact distance from Earth, but many think it is about 2,600 light-years away (see Light-year ). That would mean Deneb is about 160,000 times as bright as the sun. Deneb appears bluish-white due to its extremely high surface temperature approaching 15,000 °F (8300 °C). Deneb is often classified as a blue-white supergiant, a class of star that burns much hotter and brighter than the sun. Deneb’s diameter is about 200 times that of the sun.
