MICHELE NORRIS, Host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Michele Norris.
MELISSA BLOCK, Host:
And I'm Melissa Block.
The White House has ordered the military to shoot down a malfunctioning U.S. spy satellite that was expected to crash to Earth within the next three weeks. The decision was taken after the Pentagon determined that the fuel aboard the satellite could pose a health risk if it hit a populated area.
But as NPR's Guy Raz reports, the decision may not be just about safety.
GUY RAZ: Almost everyday, something or rather many things fall from space onto the Earth. In fact, a lot of these things hit land. But only every 50 years or so, one of those bits of space debris - be it manmade or otherwise - lands close to a human.
So you might wonder why the president, late last week, gathered up his top military and space advisers and ordered them to shoot down a runaway satellite.
JAMES JEFFREY: There was enough of a risk for the president to be quite concerned about human life. And on that basis, he asked us to review our options.
RAZ: This is deputy national security adviser James Jeffrey. He came to the Pentagon today to make the announcement. The satellite - widely thought to be a highly classified spy satellite built by Lockheed - was launched in December 2006. Almost immediately after it reached orbit, the satellite malfunctioned. In short, it became useless.
Now, some time over the next three weeks, it's going to crash down onto the Earth. And this has happened before. Back in 1979, a U.S. satellite called Spylab landed in the remote desserts of Australia. When the space shuttle Columbia broke up on re-entry in 2003, it scattered parts from California to Texas.
So if the chances of the satellite hitting a person are miniscule, why destroy it? Well, General James Cartwright, vice chairman of the Joints staff says:
JAMES CARTWRIGHT: The likelihood of it hitting the land or a person as a hunk of metal or material is relatively low. It's the hydrazine here that is the distinguishing characteristic.
RAZ: Hydrazine is a propellant fuel used aboard rockets. It's toxic, similar to ammonia or chlorine. But to die from hydrazine exposure would require standing around and breathing it in for hours. And it dissipates and evaporates pretty quickly. Which is why skeptics of the Pentagon's decision to knock the satellite out of the sky suspected has less to do with safety and more to do with keeping classified technology out of the hands of foreign competitors, a notion General Cartwright denies.
CARTWRIGHT: Now, there's some question about the classified side of this. That is really not an issue. Once you go through the atmosphere and the heating and the burning, that would not be an issue in this case. It would not justify using a missile to take it and break it up further.
RAZ: The Pentagon says its window to take down a satellite begins sometime within the next 10 days.
Guy Raz, NPR News, the Pentagon.