| BY Draconis star |
|
A type of flare star in which there are small regular variations in brightness during the quiet phase between flares. The group is named after its eighth magnitude prototype. BY Draconis stars are red dwarfs, of spectral type K or M. Of those known, a high proportion are definitely in binary systems. The variability, which amounts to no more than a few hundredths of a magnitude in a maximum period of a few days, is thought to be due to a luminous spot on the surface of the rotating star. See also: UV Ceti star. |