On average, a piece of space junk the size of Kosmos 482, with a mass of about a half-ton, falls into the atmosphere about once per week. What's different this time is that Kosmos 482 was designed to land on Venus, with a titanium heat shield built to withstand scorching temperatures, and structures engineered to survive atmospheric pressures nearly 100 times higher than Earth's.
So, there's a good chance the spacecraft will survive the extreme forces it encounters during its plunge through the atmosphere. Typically, space debris breaks apart and burns up during reentry, with only a small fraction of material reaching the Earth's surface. The European Space Agency, one of several institutions that track space debris, says Kosmos 482 is "highly likely" to reach Earth's surface in one piece.
As of Thursday, expert predictions centered on a likely reentry of Kosmos 482 early Saturday. But reentry forecasts have large margins of error. Small variations in the density of the upper atmosphere driven by solar activity could bring down the spacecraft sooner or later than expected. (...)
If you go through most of your days without worrying about space junk falling on you, there's little reason for serious alarm now. The Aerospace Corporation says any one individual on Earth is "far likelier" to be struck by lightning than to be injured by Kosmos 482. The US government's safety threshold for uncontrolled reentries requires the risk of a serious injury or death on the ground to be less than 1 in 10,000. The Aerospace Corporation projects the risk of at least one injury or fatality from Kosmos 482 to be 0.4 in 10,000 if the descent craft reaches the surface intact.
If you find yourself along one of the lines on this map, perhaps it's worth keeping track of Kosmos 482 over the next couple of days—out of curiosity more than worry. Chances are the spacecraft will fall into the ocean or over an unpopulated area.
But what happens in the unlikely event that Kosmos 482 winds up in your yard? "If Kosmos defies the odds and does land in your yard, please don’t touch it!" the Aerospace Corporation said. "It could potentially be hazardous, and it is best to notify your local authorities.
by Stephan Clark, Ars Technica | Read more:
Image: Aerospace Corporation[ed, Don't look up.]
