Pierre Auger Project

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9979239CroninScientists love a mystery, because solving a mystery in nature means the opportunity to learn something new about the universe. High-energy cosmic rays are just such a mystery. Where they come from, how they get their energy, and how they get here is not known. The highest-energy cosmic rays have a hundred million times more energy than the particles produced in the world's most powerful particle accelerator. Something out there -- no one knows what -- is hurling incredibly energetic particles around the universe. Do these particles come from some unknown super-powerful cosmic explosion? From a huge black hole sucking stars to their violent deaths? From colliding galaxies? From the collapse of massive invisible relics from the origin of the universe?Each second, about 200 cosmic ray particles with energies of a few million electron volts strike every square meter of the earth. While these low-energy cosmic rays are plentiful, cosmic rays at higher energies are far rarer. Above the energy of 10^18 eV, only one particle each week falls on an area of one square kilometer. Above the energy of 10^20 eV, only one particle falls on a square kilometer in a century! To find and measure these rare events, a high-energy cosmic ray study needs a truly giant detector. This is the instrument proposed by the Pierre Auger collaboration.The Pierre Auger Project will construct two 3000 square kilometer grids of detectors spaced at 1.5 kilometer intervals. An array in the Southern Hemisphere will attempt to track high-energy cosmic rays to their unknown sources.This project is supported jointly by the Division of Physics and the Office of Multidisciplinary Activities of the Mathematical and Physical Sciences Directorate.