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An elliptical orbit describes the path of a celestial body, such as a planet, revolving around a central mass like the Sun. This path is not a perfect circle but an ellipse, a closed curve where the sum of the distances from any point on the curve to two fixed points (foci) is constant. The Sun is located at one of these foci.12

Key characteristics of an elliptical orbit include:
* Perihelion: The point in the orbit closest to the Sun.23
* Aphelion: The point in the orbit farthest from the Sun.23
* Eccentricity: A measure of how much the orbit deviates from a perfect circle. An eccentricity of 0 is a circle, while values closer to 1 indicate a more elongated ellipse.241

Johannes Kepler's laws of planetary motion, determined from observational data, established that planets move in elliptical orbits around the Sun.2

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