A three-pound piece of metal was found lying on the floor of a Massachusetts warehouse on Thursday (Dec. 1). What made this remarkable was the gaping hole discovered directly above it in the roof.
"We don't know when exactly it fell, but we found it at 11 o'clock [a.m.]," Andrew McWilliams, an employee of Michael's Wholesale Furniture Distributors in Plymouth, Mass., told Life's Little Mysteries.
The chunk of metal appears about the same size and shape as a tall, skinny soda can, but the silvery cylinder has a tarnished look to it.
The workers reported their find to the Federal Aviation Administration (FAA), which promptly sent an inspector to investigate. All parties initially guessed that the piece of metal may have fallen off a passing plane, but the FAA later ruled out that possibility, according to CBS Boston.
"We have no idea what it is. At this point, we can only speculate. No clue," said Plymouth police Capt. John Rogers. "This would have had to come through with some significant force or velocity to get through the warehouse roof and cause damage." [See the damage]
One possibility is that the metal chunk may have fallen from space. There are approximately 20,000 bits of manmade space junk in low-Earth orbit that are as big as or bigger than the chunk that crashed through the warehouse. These usually burn up during re-entry when they fall into Earth's atmosphere, but sizable pieces occasionally make it to the ground.
McWilliams said the FAA "confiscated" the piece of debris and is continuing to investigate its source.
This story was provided by Life's Little Mysteries, a sister site to SPACE.com. Follow Natalie Wolchover on Twitter @nattyover. Follow Life's Little Mysteries on Twitter @llmysteries, then join us on Facebook.