Researchers said on Thursday that they had discovered twin-lobed radio jets they suspect were formed when the universe was 1.2 billion years old, stretching at least twice the length of the Milky Way galaxy.

These jets become elusive the farther back in time astronomers try to look because of the so-called cosmic microwave background. The ancient radiation, the earliest fossil of light from 380,000 years after the Big Bang, tends to swamp out more subtle signals.

The giant jet flips the script on the origins of these structures, which were once thought to be linked only to extremely large black holes.