The semi major axis is a measurement used in planetary science to describe the size and shape of an orbit. It is the longest distance between the center of an ellipse and one of its two foci.
The semi major axis can be calculated by taking the average of the periapsis (closest point to the focus) and apoapsis (farthest point from the focus) distances of an orbit. It can also be calculated using Kepler's third law, which relates the semi major axis to the orbital period and the masses of the two bodies.
The semi major axis provides information about the size and shape of a planet's orbit. It helps determine the distance of a planet from its star, the eccentricity of its orbit, and the orbital period.
The semi major axis plays a crucial role in determining a planet's climate. A smaller semi major axis results in a shorter orbital period and closer proximity to the star, leading to higher temperatures and potentially more extreme weather. A larger semi major axis leads to a longer orbital period and colder temperatures.
Yes, the semi major axis of a planet's orbit can change over time due to gravitational interactions with other objects or forces such as tides. This can result in changes in the planet's orbital period and potentially alter its climate. However, the semi major axis of a planet's orbit is generally considered to be stable over long periods of time.
