Fermi telescope finds cosmic ray machine
Italian technology helps pinpoint particle-charging supernova
08 January, 21:57
(ANSA) - Rome, January 7 - A NASA space telescope using Italian technology has discovered an interstellar ''engine'' bombarding the Earth with cosmic rays, scientists said Thursday.
Launched in June 2008, the Fermi telescope has found the first evidence for a long-held theory that the shells of energy and matter left behind by stellar explosions serve as accelerators for the high-energy particles that make up cosmic rays.
''This is a big step forward,'' said Italian Astrophysics Institute researcher Patrizia Caraveo, a member of the international team of scientists behind the discovery.
''We knew that the ultra high-energy protons and electrons permeating our galaxy were being accelerated by something, but we weren't positive what,'' she said. Caraeo explained that the cosmic ray motor is a star much larger than the Sun which exploded thousands of years ago leaving behind a magnetic cloud known as W44.
She said that the find was especially fortuitous, because of the rarity of that breed of supernova remnant.
''You can count the ones observable from Earth on one hand,'' she said.
Director of the Italian Nuclear Physics Institute, Ronaldo Bellazzini, also involved in the project, noted that the findings supported theories first put forward by the telescope's namesake.
Italian physicist Enrico Fermi (1901-1954) lent his name to a theory of charged particle acceleration which has long been used to explain how cosmic rays acquire such high energies.
According to Bellazzini, the particles composing the rays put even the largest manmade particle accelerators to shame, achieving energies billions of times greater. Though scientists are learning more about the mechanics of cosmic ray particles, their effects on the Earth are largely disputed.
Some researchers theorize they may influence the weather while others believe they could also affect climate change.
Photo: a supernova remnant
