Three and a half kilometers beneath the Mediterranean Sea, around 80km off the coast of Sicily, lies half of a very unusual telescope called KM3NeT.

The enormous device is still under construction, but today the telescope’s scientific team announced they have already detected a particle from outer space with a staggering amount of energy.

In fact, as the team report in Nature, they found the most energetic neutrino anyone has ever seen—and it represents a tremendous leap forward in exploring the uncharted waters of the extreme universe.