#3053: KM3NeT

XKCD comic, described below.
Transcript

[Ponytail is pointing behind her towards a drop down screen as she adresses Cueball and Megan in front of her. On the screen is a panel showing a side view of a deep-water telescope. It shows four series of circles stringed together attached to the rough bedrock, so the circles are floating above the bedrock, but far beneath the surface. Waves are drawn just beneath the top of the panel on the screen, indicating the surface of the ocean.]

Ponytail: The KM3NeT deep-water telescope detects the flashes of Cherenkov light from neutrino interactions.

Cueball: How do you know you aren't just seeing bioluminescent fish?

Ponytail: Cherenkov radiation is only emitted when things exceed the local speed of light, so it can't be produced by under-c life.

(Sourced from explainxkcd.com)

Unfortunately, KM3NeT led to the discovery of the Pauli anglerfish, which emits Cherenkov radiation to prey on neutrino researchers.

ExplainOriginal