Spy satellite to crash in early March

February 8, 2008 The only problem is, no one seems to have the faintest idea as to where debris from the 5,000-pound spacecraft will land.

The military satellite was launched in December 2006. It carries a sophisticated and secret imaging sensor. It experienced a power and computer failure almost immediately after entering space.

The satellite has been wandering in orbit in a random path ever since. Without power, the satellite was doomed to eventually crash into the Earth's atmosphere and break up.

The U.S. is worried that pieces of the satellite may land in another country, allowing that nation's leaders to examine secret American technology.

U.S. trackers will have a better idea where US 193 is going when it begins its descent into the atmosphere, 59 miles above the planet. It will burn up from the immense friction with atmospheric molecules and fall within 30 minutes. People on the ground near the entry point may be able to see flares from the craft.

The debris could be scattered over several hundred miles. Some of it could be hazardous. The satellite contains the toxic rocket fuel hydrazine.

Short-term exposure to hydrazine could cause coughin, irritated throat and lungs, convulsions, tremors and seizures. Long-term exposure could damage the liver, kidney and reproductive organs.

Bottom line: if the satellite happens to fall in your neighborhood, don't touch it!

Chances are US 193 will fall into the ocean. More than two-thirds of the planet is covered with water.

Seventeen thousand man-made objects have re-entered the Earth's atmosphere over the last 50 years. Most burned up.

The largest uncontrolled re-entry by a NASA spacecraft was Skylab. It weighed 78 tons, and dropped harmlessly over the Indian Ocean and a remote section of Australia in 1979.