Back in 1977, astronomers from the Ohio State University picked up a powerful signal originating from space using their Big Ear radio telescope that some called our first encounter with an alien broadcast, according to New Scientist. Dubbed the "Wow!" signal, it was discovered by focusing on a portion of the radio spectrum that closely resembles hydrogen, according to Gizmodo. However, a new study is putting that spectacular theory to rest, asserting that the signal stemmed from a pair of comets passing the Earth, according to Antonio Paris, an astronomer from St. Petersburg College.
Paris claims the signal was likely produced by one or two passing comets known as 266P/Christensen and P/2008 Y2. Paris says that comets are known to release large amounts of hydrogen when making their way past the sun and as these comets flew through the solar system, ultraviolet rays likely disturbed their surface and lead to the release of a hydrogen cloud that extended for miles.
Not everyone agrees with Paris, though. James Bauer of NASA's Jet Propulsion Laboratory claims he is unsure whether the emissions from a comet's hydrogen clouds would have been strong enough to create the mysterious Wow! Signal, according to the Daily Mail.
"If comets were radio-bright at 21 centimetres, I would be puzzled as to why they aren't observed more often at those wavelengths," he said.
Paris' hypothesis will be put to the test when the 266P/Christensen comet passes through the same area of space in January of 2017 and P/2008 Y2 makes its way through our orbit in January of 2018.
"The hypothesis must be tested before it is ruled out," he said.