Ratio of the distance between the foci and the Longest diameter of an ellipse; the line from one side of an ellipse to the other that passes through the foci. of an ellipse (planetary The elliptical path of one body around another, typically the path of a small body around a much larger body. However, depending on the mass distribution of the objects, they may rotate around an empty spot in space • The Moon orbits around the Earth. • The Earth orbits around). Eccentricity is:
where ra = Point in an object’s orbit farthest from a planetary body. distance and rp = periapsis distance.
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