A team of astronomers has discovered a massive ancient explosion that shows itself today as supernovae far more luminous than normal.

At ten billion light years away, the supernovae are the most distant ever recorded and they are also hundreds times brighter than average. The Supernova Legacy Survey (SNLS) research team will publish their study Friday in the Astrophysical Journal.

"At first, we had no idea what these things were, even whether they were supernovae or whether they were in our galaxy or a distant one," lead author D. Andrew Howell, a staff scientist at Las Cumbres Observatory Global Telescope Network (LCOGT) and adjunct faculty at UC Santa Barbara (UCSB), said in a press release. "I showed the observations at a conference, and everyone was baffled. Nobody guessed they were distant supernovae because it would have made the energies mind-bogglingly large. We thought it was impossible."

The supernovae are an emerging class known as "superluminous supernovae." Study co-author Daniel Kasen, of UC Berkeley and Lawrence Berkeley National Lab, said models he created explained that the exploding star was only a few times larger than the sun and made up mostly of hydrogen and oxygen.

"What may have made this star special was an extremely rapid rotation," Kasen said. "When it ultimately died, the collapsing core could have spun up a magnetar like a giant top. That enormous spin energy would then be unleashed in a magnetic fury."

Howell likened the discovery to how archaeologists dig up fossils, only in this case, the searching is through the endless boundaries of space.

"These are the dinosaurs of supernovae," Howell said. "They are all but extinct today, but they were more common in the early universe. Luckily we can use our telescopes to look back in time and study their fossil light. We hope to find many more of these kinds of supernovae with ongoing and future surveys."