The Planck space telescope has made the first conclusive detection of a bridge of hot gas connecting a pair of galaxy clusters across 10 million light-years of intergalactic space. 

"Planck is helping to reveal hidden material between galaxy clusters that we couldn't see clearly before," said James Bartlett of NASA's Jet Propulsion Laboratory, Pasadena, Calif., a member of the U.S. Planck science team. Planck is a European Space Agency mission with significant participation from NASA.