When the universe was still young, they were already dying.

The first stars ever to grace the cosmos with light were brutish monsters, so the story believed by most astronomers goes, lumbering clouds of hydrogen and helium hundreds of times more massive than the Sun. They lived fast and bright and died hard, exploding or collapsing into massive black holes less than a billion years after the Big Bang, never to be seen again.

But they might have left something behind, a buzz of radio waves emitted by high-energy particles spit from the doomed gas swirling around those black holes.

Has that buzz, a cry from the vanished ancestors of our Sun, now been heard?

That is at least one “wildly speculative” explanation, said Alan Kogut of the Goddard Space Flight Center, for a mysterious radio static that seems to pervade the universe. He led a team that discovered the signal accidentally while scanning the skies in July 2006 with a set of sensitive radio receivers called Arcade lofted 21 miles high on a balloon.

The signal manifests itself as a puzzling excess at certain frequencies of a fog of microwaves that permeates the cosmos and is probably left over from the Big Bang itself. It suggests that something is pumping large amounts of extra energy  about six times more than can be accounted for by all the galaxies known and unknown  into the universe.