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If the orbit of Earth is elliptical and the Sun is one foci, where is the second foci?


The second distance is in an almost mirrored position to where the Sun is in the first foci. Since the planets exert gravity on the Sun, both the Sun and planets move around each other with the center of mass at the focus, but since the Sun accounts for 99.9% of the mass of the solar system, the Sun is basically one of the foci. 




Categories: Flight Dynamics