Array of radio telescopes reveals explosion on the surface of a hot dead star

An international group of researchers observed a source of variable gamma rays identified in 2010 by the NASA satellite Fermi. They used a technique called VLBI, that combines data from several radio telescopes on Earth, to produce the sharpest images to date. Surprisingly, the source of gamma rays was a symbiotic nova, a peculiar stellar system known to astronomers as V407 Cyg. The result, with first author Marcello Giroletti (National Institute of Astrophysics INAF, Italy), has been presented ...