MINOS neutrino experiment steel plate. View of one of the 484 giant steel plates for the MINOS (Main Injector Neutrino Oscillation Search) experiment. The plate, which is 8 metres in diameter but just 25.4 mm thick, will be placed in the Soudan iron mine in Minnesota, USA. MINOS will be the target for a beam of neutrinos generated 730 km away at the Main Injector particle accelerator at Fermilab, near Chicago. MINOS will be 20 metres long, with thin sheets of scintillator material between the plates. The experiment aims to study whether neutrinos oscillate from one type to another. If they do, it will help to prove that neutrinos have mass. Photographed in 1998. The guy in the picture is BOB BERNSTEIN.