The brilliant blue light we associate with radioactive fuel rods in a reactor’s pool is due to particles moving through a local medium faster than the speed of light.  This is the Cherenkov Effect, and with a ring detector, radiologists at the Dartmouth-Hitchcock Medical Center (Lebanon, NH) have been able to see the radiation beams of a linear accelerator kill tumor cells in real time. Better targeting, effectiveness of treatment, and control over dosage errors are possible benefits with this method.  Soviet physicist Pavel Cherenkov shared the 1958 Nobel Prize for his namesake discovery.  MORE