The event, which has only just come to light, occurred off the coast of Brazil at 13:55 GMT on 6 February.
As it burned up, the space rock released the equivalent of 13,000 tonnes of TNT.
This makes it the most powerful event of its kind since an object exploded over Chelyabinsk in Russia in 2013.
That blast was much bigger, releasing the equivalent of 500,000 tonnes of TNT.
More than 1,000 people were injured in that incident on 15 February three years ago, most from flying glass from shattered windows.
But the fireball over the Atlantic probably went unnoticed; it burnt up about 30km above the ocean surface, 1,000km off the Brazilian coast. Read more on bbc.