A broken U.S. spy satellite filled with toxic fuel is tumbling toward the earth. The Pentagon says it wants to shoot it down with a high tech missile for safety and environmental reasons.

The spy satellite -- USA 193 -- it's currently drifting about 130 miles above the Earth.

If the clouds clear out Saturday evening it could be quite visible high above Austin around 7:04 p.m.

"Tomorrow night will be the really good night," said Ed Cannon, an amateur satellite observer. "it will be nearly straight up tomorrow night."

The satellite was launched in December of 2006. Its main computer failed almost immediately, making it uncontrollable. Its fuel tank contains 1,000 pounds of a toxic fuel called Hydrazine.

The U.S. government says it hopes to blast it with a missile from a ship in the Pacific Ocean next week so that the debris lands over water.

Cannon says it's not likely to injure people.

"The chances of it hitting a populated area are really very remote, but it could happen," he said.

Rodger Baker, a senior analyst with the private intelligence agency Stratfor in Austin, says the real reason the U.S. government is going to shoot down the spy satellite is to send a message to China.

"If the U.S. and the Chinese ever went to war, the U.S. has a significant advantage in space. All of our guided munitions, communications and the ability to move our military all of the world is really dependent on space," Baker said.

Baker believes the U.S. is using the stray satellite to justify an anti-satellite test and to prove dominance in space.

"I don't think the U.S. would be carrying this out if they weren't pretty confident that it will be able to shoot the satellite out of the sky. The worst thing that can happen is if the U.S. launches a couple of interceptors and they totally miss," he said.

If the mission fails the satellite is expected to crash to the Earth the first week in March.