No worries, water is a very good radiation blocker. You could swim on the surface safely

and you could drink it....no really!

It's true! I grew up right across the street from this one

https://en.wikipedia.org/wiki/Reed_Research_Reactor

and I don't notice any extra eyes or wang problems..

It happens to all of us once in a while..

I only learned the details of Cherenkov radiation in grad school physics. The derivation of the angle of the cone is pretty cool.

In a given (linear) medium, waves have a fixed propagation speed. If something moves through the medium, it makes wakes that travel at that speed. The pattern that the waves make are very different depending on whether the "something" moves slower or faster than the wave speed (or exactly at the wave speed).

People are used to thinking that the speed of light is a fixed maximum, but this is only true in vacuum. In a medium (in this case water), the propagation speed of light waves is slower than in vacuum, but objects (in this case charged particles) can still go faster than the light waves (though they still go slower than c). The pattern of light waves that you see is very different depending on whether the objects move slower or faster than the propagation speed of the light.

Cherenkov light is specifically when a charged particle moves through a medium faster than light waves propagating in that medium.

Yeah but how does that generate light?
Thanks btw!

That is cool! Thank you for sharing that.