A fairly sizeable meteor exploded over the South Atlantic Ocean earlier this month and went mostly unnoticed.

Ron Baalke, of NASA's Jet Propulsion Laboratory, first reported the meteor impact and noted it was the "largest since Cheylabinsk." But whereas the Cheylabinsk meteor impact packed a 440-kiloton energy output, the recent one accounted for 13 kilotons of energy.

Phil Plait wrote for Slate that there were a few key reasons why the recent meteor impact went unnoticed for several weeks.

"As impacts go, this was pretty small," he wrote. "After all, you didn't even hear about until weeks after it occurred. Events this size aren't too big a concern. Had it happened over a populated area it, would've rattled some windows and probably terrified a lot of people, but I don't think it would've done any real damage."

It was easily substantial enough to go on record for NASA's Near-Earth Object program, as the last two impacts to surpass one kiloton were reported last June and in Sept. 2014. NASA refers to these NEOs as "fireballs," but for a reason more than just its appearance.

"Objects causing fireballs are usually not large enough to survive passage through the Earth's atmosphere intact, although fragments, or meteorites, are sometimes recovered on the ground," read the program's website. "An event with an energy equivalent of one thousand tons of TNT explosives is termed a kiloton."