Shapes of Orbits

The paths, or orbits, of celestial bodies are curved because of the gravitational attraction of other bodies. Early astronomers believed that all orbits consisted of combinations of circles until Johannes Kepler used the data of Tycho Brahe to establish that the planets follow elliptical paths around the sun. Other kinds of orbit, such as those of some comets, are parabolic or hyperbolic in shape. An object following such an orbit is not captured by the sun, but escapes from it.

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Orbit

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