Kepler's Second Law, the Law of Areas states:
The line joining the planet to the sun sweeps over equal areas over equal
time intervals.
When a satellite orbits, the line joining it to the Earth, the line
joining it to the Earth sweeps over equal areas in equal periods of time.
If areas 1, 2, and 3 are equal, times 1, 2, and 3 are also equal.
Therefore, the speed of the satellite changes depending on its distance
from the center of the Earth.