Before he was an astrophysicist at the St Petersburg College, Paris was an analyst for the US Department of Defence. “I have this investigative background, so I approached the ‘Wow!’ signal as I’m going back to the crime scene,” he told me over Skype. “It’s a cold case, so I went to various [astronomical] databases to find culprits or suspects that were at this crime scene at the time.”

He didn’t find aliens but he did find two suspicious looking comets.

Known as 266P/Christensen and 335P/Gibbs, they have never been investigated before because they were only discovered in 2006 and 2008 respectively. Paris found that they were both in the vicinity of Chi Sagittarii on the day that the ‘Wow!’ signal was detected.

This could be significant because comets are surrounded by clouds of hydrogen gas that are millions of kilometres in diameter. The ‘Wow!’ signal itself was detected by Ehman at 1420MHz, which is a radio frequency that hydrogen naturally emits. He published his idea at the beginning of this year.