Aphelion and Perihelion

Aphelion is the greatest distance between a planet or other body and the Sun. Perihelion is the closest distance from the Sun. Objects move slowest in their orbits when they are aphelion and fastest when at perihelion.

Radio Programs

More Moon and Company The Moon and a supergiant Friday, January 4, 2008

Earth at Perihelion A tricky bit of stellar geography Tuesday, January 1, 2008

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A black hole devours a companion

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Aphelion and Perihelion

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