Eclipsing Binary Stars

Eclipsing Binary Star
728Kb QuickTime Movie
53Kb MPEG Movie
288Kb Animated GIF
This movie simulates an eclipsing binary star system consisting of an A0v primary and G5v secondary in a circular orbit about each other. The orbital plane is tilted with respect to the line of sight by 6°. The top half of the frame shows the appearance of the two stars, with the red dot marking the center of mass of the system (just outside the radius of the blueish A0v primary star). The light curve of the total system is traced out in the lower panel as they orbit. Two orbits full orbits are shown, with a red marker used on the light curve to show the current location.

Notice that the deepest eclipse occurs when the secondary is in front of the primary. This is because of the nearly factor of two greater effective temperature of the primary (10,000K compared to 5,500K). Since surface brightness scales like T4, more light is blocked when the secondary is blocking part of the primary, than when the primary completely blocks the secondary.

[Credit: R. Pogge, OSU]

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Updated: 2007 November 3 [rwp]

Copyright Richard W. Pogge, All Rights Reserved.