Fermi telescope detects gamma-rays from Cygnus X-3
on November 26, 2009
In Cygnus X-3, a hot, massive star is paired with a compact object — either a neutron star or a black hole — that blasts twin radio-emitting jets of matter into space at more than half the speed of light. Astronomers call these systems microquasars. Their properties — strong emission across a broad range of wavelengths, rapid brightness changes, and radio jets — resemble miniature versions of distant galaxies (called quasars and blazars) whose emissions are thought to be powered by enormous black holes. Cygnus X-3, first detected in 1966 as among the sky's strongest X-ray sources, was also one of the earliest claimed gamma-ray sources. Efforts to confirm those observations helped spur the development of improved gamma-ray detectors, a legacy culminating in the Large Area Telescope (LAT) aboard NASA's Fermi Gamma-ray Space Telescope.