A Mysterious Machine to Catch Mysterious Particles
If dark matter exists, it make take the form of Weakly Interacting Massive Particles (WIMPs). These particles have never been measured, but scientists at the Gran Sasso National Laboratory in Italy will attempt to do so in this round tank, which is 25 m in diameter. Photographer Enrico Sacchetti was allowed to photograph the tank before it was filled with water and sealed. A container full of liquid xenon (at top) has been lowered into the tank, and if a WIMP hits the xenon atoms, it will release a flash of light, which will be detected by the sensors in the tank.