kiertotason

Kiertotason is a Finnish term that translates to orbital plane in English. It refers to the imaginary flat surface in three-dimensional space that contains the orbit of a celestial body, such as a planet, moon, asteroid, or comet. This plane is defined by the direction of motion of the orbiting object.

For planets in our solar system, their orbital planes are all tilted relative to the ecliptic, which is the Earth's orbital plane. The degree of this tilt is known as inclination. While the planets orbit the Sun, their orbits are not perfectly aligned. For instance, Mercury has a relatively high inclination compared to other planets, meaning its orbit is more tilted with respect to the ecliptic.

The concept of the orbital plane is fundamental in celestial mechanics and astronomy. It is used to describe and predict the positions and movements of celestial objects. When discussing the orbit of an object, its inclination and the orientation of its orbital plane relative to a reference plane are crucial parameters.

Understanding orbital planes helps astronomers in various calculations, including determining when an object might be visible, predicting eclipses, and studying the formation and evolution of planetary systems. The gravitational influence of larger bodies can also cause slight perturbations and changes in the orientation of these orbital planes over long periods.