When a star goes behind another, there will be a reduction of total luminosity. Since the motion of the stars is periodic, the light curve will also be periodic.

• 当子星经过伴星的前后,由于两星重叠,所以整体亮度会下跌,再加上双星的运动是周期性的,所以光变曲线亦会出现同一周期的变动。