A semi major axis is a measurement used in orbital mechanics to describe the size of an elliptical orbit. It is the longest radius of an ellipse, extending from the center to one of the farthest points on the ellipse.
The semi major axis can be calculated by taking the average of the closest and farthest distances from the center of the ellipse. This is also known as the semi major axis length.
The semi major axis is typically measured in astronomical units (AU) or meters (m). In astronomy, 1 AU is equal to the average distance between the Earth and the Sun, which is approximately 149.6 million kilometers or 93 million miles.
The semi major axis is an important measurement in orbital mechanics because it helps determine the shape, size, and orientation of an elliptical orbit. It is also used in calculating the orbital period and speed of an object.
Yes, the semi major axis can change due to external forces such as gravitational interactions with other objects in the system. It can also change over time due to factors such as tidal forces or atmospheric drag.
