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Where is the Sun located within a planet’s elliptical orbit?
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Celestial mechanics
Ptolemaic diagram of a geocentric system, from the star atlas Harmonia Macrocosmica by the cartographer Andreas Cellarius, 1660.
In the context of celestial mechanics, the Sun is located at one of the two foci of the ellipse that defines a planet’s orbit.123
According to Kepler’s first law of planetary motion, all planets move in elliptical paths with the Sun positioned at one focus. This arrangement is a fundamental principle in understanding the motion of bodies within the solar system, as the Sun serves as the central attracting mass around which the planets revolve.123