NASA Fermi Gamma-ray Space Telescope Reveals A Cosmic-ray Cocoon

Study using data from NASA’s Fermi Gamma-ray Space Telescope finds that the tumult of star birth and death in Cygnus X has managed to corral fast-moving particles called cosmic rays. Cosmic rays are subatomic particles mainly protons that move through space at nearly the speed of light. In their journey across the galaxy, the particles are deflected by magnetic fields, which scramble their paths and make it impossible to backtrack the particles to their sources. But when cosmic rays collide with interstellar gas, they produce gamma rays the most energetic and penetrating form of light that travel to us straight from the source. By tracing gamma ray signals throughout the galaxy, Fermi’s Large Area Telescope (LAT) is helping astronomers 

understand the sources of cosmic rays and how they’re accelerated to such high speeds. In fact, this is one of the mission’s key goals. The Cygnus X star factory is located about 4500 light-years away, is believed to contain enough raw material to make two million stars like our sun. Within it are many young star clusters and several sprawling groups of related O- and B-type stars, called OB associations. Astronomers estimate that the association’s total stellar mass is 30,000 times that of our sun, making Cygnus OB2 the largest object of its type within 6,500 light-years.