BY Draconis variable

The name comes from the archetype for this category of variable star system, BY Draconis.

They exhibit variations in their luminosity due to rotation of the star coupled with starspots, and other chromospheric activity.

For the star BY Draconis the shape of the light curve over a period remained similar for a month.

The variability of BY Draconis itself was discovered in 1966 and studied in detail by Pavel Fedorovich Chugainov over the period 1973–1976.

[2] Some of these stars may exhibit flares, resulting in additional variations of the UV Ceti type.