Are aliens trying to contact Earth? Scientists discover a mysterious stellar object that emits a five-minute pulse every 22 minutes - and they have no idea what it is

If aliens were to contact Earth, what would it sound like? Such a scenario has been imagined countless times in science fiction but in reality we have no proof extraterrestrials even exist. That hasn't dampened the excitement that an advanced civilisation might be out there, however, and the discovery of a mysterious stellar object which emits a five-minute pulse every 22 minutes will only serve to intensify that. What's more, the scientists who detected it aren't 100 per cent sure what it is. An international team of astronomers led by Australia's Curtin University think it could be an ultra-long period magnetar -- a rare type of star with the most powerful known magnetic fields in the universe.