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Perihelion

Perihelion is the point in the orbit of an object where it is closest to the Sun. In astronomy, this term is commonly used to describe the position of planets, comets, and asteroids in relation to the Sun. The perihelion occurs at a specific distance in the elliptical orbit of the celestial body, which varies for different objects. The counterpart of perihelion is aphelion, which is the point in the orbit where the object is farthest from the Sun. The distances of perihelion and aphelion can significantly affect the object’s speed and temperature as it moves through its orbit, according to Kepler’s laws of planetary motion. For Earth, perihelion occurs around early January each year. The concept is essential for understanding orbital mechanics and the dynamics of celestial bodies in the solar system.