Cerenkov radiation, electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium, characterizes the radioactivity of fuel rods, giving nuclear reactors their iconic blue glow.

The Idaho National Laboratory provides thousands of jobs in southern Idaho, a point Congressman Mike Simpson is eager to stress in his reelection bid. Now, if you’re imagining a building full of people in lab coats, think again. The “lab” is a smattering of nuclear research facilities over nearly 900 square miles of desert. The above photo was snapped just after we passed a sign on the road telling us we were entering the lab.