With further work the true inclination of the orbit, and the true masses of the two stellar components can be calculated. From analysing the shape of such light curves the stellar radii can be calculated as can the effective temperature of each component. If the radius and temperature are known, the absolute brightness or luminosity of a star can be calculated. In very close binaries, the stars gravitationally distort each other into egg-shaped objects. These stars have particularly dynamic light curves which are continuously changing, partially due to the eclipses, and partially due to the unusual geometry of the stars themselves, which present a different aspect to the line of sight as the system rotates.
Many spectacular results occur in close binary systems especially as the stars age.
This results in the outer envelope expanding to massively increase the radius and a simultaneous reduction in surface temperature. While for a single star, this process often results in the eventual formation of a planetary nebula, in a close binary the system is more complex as shown in the graphic above. This creates what is known as Roche Lobes around the two components. Things get really interesting when the more evolved component of a semi-detached binary expands enough to fill its Roche Lobe. Matter can then flow freely from the more evolved component to the less evolved component.