Subscribe and 🔔 to OFFICIAL BBC YouTube 👉 https://bit.ly/2IXqEIn Stream original BBC programmes FIRST on BBC iPlayer 👉 https://bbc.in/2J18jYJ Programme website: http://www.bbc.co.uk/programmes/p0276pxp Brian Cox explains the mysterious 'Wow!' radio signal picked up in 1977. Scientists speculated ...