This portal provides basic knowledge on astronomy and highlights current research projects and collaborations in Switzerland.

Image: ESO

Orbital period (planet)

The orbital period refers to the sidereal orbital period. This corresponds to the time it takes for a planet to orbit the Sun once and return to the same position as at the beginning. Colloquially, we call this a year on Earth. Consequently, a year is shorter on planets closer to the Sun than ours and longer on planets farther away from the Sun.