LEILA FADEL, HOST:
A family in Naples, Fla., got quite a surprise last month when a chunk of metal crashed through the roof of their home.
ALEJANDRO OTERO: It was a tremendous sound, and it almost hit my son. He was two rooms over and heard it all.
FADEL: Alejandro Otero talked to WINK when it happened, and now they finally have an answer from NASA.
A MARTÍNEZ, HOST:
Yeah. Listen to this. The space agency issued a statement saying the metal was from a pallet of old batteries tossed out of the International Space Station three years ago.
FADEL: Well, it was supposed to disintegrate in the atmosphere, but Moriba Jah at the University of Texas at Austin says it doesn't always go as planned.
MORIBA JAH: There's probably over a dozen things, like dead satellites and pieces of space debris, that reenter the atmosphere daily. A lot of those are small. By and large, those mostly burn up, but larger things could definitely survive and make it to the surface, like this thing did.
FADEL: Jah is a professor in the school's aerospace engineering department.
JAH: My job is to find ways to understand and predict the behavior of human-made objects in orbit.
MARTÍNEZ: Jah says the federal officials who keep track of space debris can't always predict where something will land, although they can calculate roughly when it'll come down and the probability that a hunk of space junk could hurt someone.
FADEL: If it's less than a one-in-10,000th chance, Jah says it's usually considered safe enough not to intervene.
JAH: I don't know about you, but if I'm driving on a freeway and somebody says, hey, there's about a one-in-10,000 chance that a bridge will fall on you, that doesn't make me feel warm and fuzzy inside to get into a car.
MARTÍNEZ: Me neither. Human-made space objects aren't built to last, but Jah says there are probably safer ways to dispose of them.
JAH: There's no reason why NASA and the U.S. government can't say, hey, we're going to do a controlled disposal so that it fully burns up in the atmosphere, and we'll design it out of a material that doesn't pollute the atmosphere in the process.
FADEL: So maybe the lesson here is don't throw junk out of your space window. In its statement, NASA says it will investigate and remains committed to mitigating risk to protect people on Earth when space hardware has to be released.
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