The point at which Earth is closest to the Sun—Perihelion—is a fascinating astronomical event defined by precise geometry and timing.

The point in early July when Earth is approximately 94.5 million miles away. Earth at perihelion – closest to sun – on January 3

The most significant educational aspect of perihelion is its relationship with the seasons.

Johannes Kepler’s First Law of Planetary Motion states that planets move in elliptical orbits with the Sun at one focus. Because of this ellipse, the distance between the Earth and the Sun fluctuates throughout the year.