Part of CERN's Large Hadron Collider, used by physicists to test theories of particle physics. It helped prove the existence of the Higgs Boson particle. It lies 175 metres deep under the French-Swiss border.
Lead ion collision at the Large Hadron Collider. This is the world's highest-energy particle accelerator. Up until now, they were colliding protons. Using lead ions, they created temperatures a million times hotter than at the centre of the Sun.