⚡️Active Nuclear Reactor Core. The blue glow is called Cherenkov radiation.⚡️ : r/CantBelieveThatsReal
Cherenkov Radiation, a phenomenon that occurs when particles travel faster than the speed of light in a given medium. It produces this gorgeous blue color, and is perfectly safe to observe. :
Cherenkov Effect is Science, Not Science Fiction | Duke Energy | Nuclear Information Center
What is Cherenkov Radiation? - Universe Today
How a particle racing through a vacuum leaves a trail of blue light