Thursday, November 26, 2009

Gamma-ray Space Telescope

In Cygnus X-3, an accretion disk surrounding a black hole or neutron star orbits close to a hot, massive star. Gamma rays (purple, in this illustration) likely arise when fast-moving electrons above and below the disk collide with the star's ultraviolet light. Fermi sees more of this emission when the disk is on the far side of its orbit.

Brighter colors indicate greater numbers of gamma rays detected in this Fermi LAT view of a region centered on the position of Cygnus X-3 (circled). The brightest sources are pulsars

This image locates the view around Cygnus X-3 within Fermi's all-sky map.