The
space roar is a radio signal from
outer space. Discovered by
NASA's Alan Kogut and his team, space roar was announced at the 213th meeting of the
American Astronomical Society on January 7, 2009. Described as a loud hiss, the team discovered the signal while trying to find traces of heat from first generation stars using an
ARCADE radiometer. This instrument is designed to detect radiation at centimeter wavelengths. Though signals from
radio galaxies have been detected before, the "space roar" sounds six times louder than what is predicted from those sources. Scientists have yet to explain its source. NASA scientists have currently ruled out primordial stars and all other known radio sources. The roar currently limits the study of the universe's earliest stars.