Elliptical Orbits

An elliptical orbit, also called an eccentric orbit, is in the shape of an ellipse. In an elliptical orbit, the satellite's velocity changes depending on where it is in its orbital path. When the satellite is in the part of its orbit closest to the Earth, it moves faster because the Earth's gravitational pull is stronger. The satellite is moving the fastest at the low point of an elliptical orbit. The low point of the orbit is called the perigee. The high point of the orbit, when the satellite is moving the slowest, is called the apogee.

An elliptical orbit can be useful to a communications satellite because it allows the satellite to travel over a specific region for a long portion of its orbit, and it is only out of contact with that region for a short time when it is zipping quickly around the other side of the Earth.

Elliptical orbit

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Last updated on: 8 August 1997.