A cosmic neutrino of unknown origins smashes energy records

Such high-energy neutrinos could offer insight into the universe’s most cataclysmic phenomena

An animation shows a collection of vertical lines strung with small bundles, like beads on strings. A red line cuts horizontally across the vertical lines, moving from right to left. As the red line passes various vertical lines, the small bundles on those lines burst with blue and orange bubbles. The background is deep blue, almost black.

In February 2023, a muon zoomed through the forest of underwater cables in a KM3NeT telescope. As the muon crossed the detector (path in red), it gave off a faint glow detected by light sensors along the cables (activated sensors in blue and orange).

KM3NeT

A neutrino from space recently plunged into the Mediterranean Sea with an energy that blows all other known neutrinos out of the water.