You almost never hear of a satellite orbiting going to the west, too expensive in fuel.

For years during the 1960's and 1970's a single satellite would orbit, and then only part of the year.

Space surveillance is the study and monitoring of satellites orbiting the earth.

There are also man-made satellites orbiting something other than the Earth.

This was the first observation of satellites orbiting another planet.

As of 2003, there are 58 known natural satellites orbiting the planet Jupiter.

"And if that's the case, sir, there are very likely additional satellites orbiting on the far side of the planet."

Altogether, about 700 functioning satellites now orbit Earth, but that number is expected to rise to 2,000 or more in coming decades.

For example, an artificial satellite orbiting around earth can be viewed as a cabin.

Four similar satellites, all launched from here earlier this year, are orbiting Earth as part of a global navigation network.