HESS begins hunt for cosmic gamma rays

4 September 2002

HESS one of the first four telescopes searching for cosmic rays

The first of four telescopes in the HESS (High Energy Stereoscopic System) project in Namibia has begun its search  for cosmic gamma rays. The telescopes are designed to detect the Cerenkov radiation created in the atmosphere when an energetic gamma ray creates a shower of charged particles (electrons and positrons). The Cerenkov radiation forms rings of light when it strikes the telescope's mirror, which consists of 382 facets. Studying high energy gamma rays, which are not deviated by interstellar magnetic fields, should reveal new sources of cosmic gamma rays and help to solve the mystery of the origin of cosmic rays. 

Credit: HESS Collaboration