One might think the sky is falling. An asteroid is scheduled to pass within a half million miles of Earth this week, and another one has a one in 75 chance of hitting Mars. Now comes news of a spent spy satellite losing altitude and expected to eventually crash land. VOA's Paul Sisco has more.

It is about the size of a school bus and weighs more than 9,000 kilograms -- a powerless U.S. spy satellite rapidly falling from orbit, heading for Earth.

"By now it is down to not much more than 100 miles (160.9 kilometers) up and is getting closer to the Earth every day by about a half a mile [0.8 kilometers]," said John Pike of

The U.S. Defense Department tracks man-made objects in space and says the satellite could reach Earth sometime before early March.

Pike remembers NASA's Skylab. Larger than this satellite, it fell from orbit, crashing into Western Australia without incident in 1979. He says, "Skylab was much larger and they had a little bit of control over Skylab, whereas this spacecraft they have no control over."

The defunct spy satellite is traveling at nearly 29,000 kilometers an hour. Because three-fourths of the planet is covered with water, there is a one in four chance the satellite will crash on land.