The Cherenkov radiation in that video is worth a watch if you haven't seen it be...

eliasmacpherson on March 14, 2011 | parent | context | favorite | on: Why I am not worried about Japan’s nuclear reactor...

The Cherenkov radiation in that video is worth a watch if you haven't seen it before. Apparently the water contains the radiation. The effect is from the electrons passing through the water faster than the speed of light could be in the water.