Namibian authorities are scratching their heads over a strange metal ball that fell out of the sky, they reveal. The ball, which weighs about 13 pounds and is 14 inches in diameter, was found lying about 60 feet away from the 12-foot-wide crater it left in the ground when it landed in mid-November. A few days earlier, locals had reported hearing small explosions, the AFP reports.
Authorities held off on announcing the find until they were sure the ball wasn’t some kind of explosive, but they’ve concluded that it’s not dangerous. They have determined that it’s hollow and constructed from a “metal alloy known to man,” and was apparently made by welding two half-balls together. Beyond that, they’re stumped, and have put in calls to NASA and the European Space Agency for an explanation. A Gawker commenter thinks he has solved the mystery, though: He believes it's a hydrazine bladder tank belonging to an unmanned rocket. Click for more. (Read more space junk stories.)