Authorization is given for the use of this information over any ham band. Please give credit for the script where credit is due. Seven numbers are required to define a satellite orbit. These numbers define an ellipse, orient it about the earth, and place the satellite on the ellipse at a particular time. In the Keplerian model, satellites orbit in an ellipse of constant shape and orientation.
Orbital elements remain a mystery to most people.
This is due to the aversion many people have to thinking in three dimensions, and second to the horrible names the ancient astronomers gave these seven simple numbers and a few related concepts. To make matters worse, sometimes several different names are used to specify the same number. A set of orbital elements is a snapshot, at a particular time, of the orbit of a satellite. Epoch is simply a number which specifies the time at which the snapshot was taken. The orbit ellipse lies in a plane known as the orbital plane.