Are alien spacecraft causing mysterious flashes?

A respected team of scientists has suggested that flashes of energy detected at the edges of the universe may be evidence of super-advanced alien spacecraft.

Fewer than two dozen of the intense radio waves have been detected in distant galaxies, billions of light years away.

Professor Avi Loeb, from Harvard University, tells PM that the radio waves are being "used by an advanced technological civilisation to propel a spacecraft".

(Image: Artist"s illustration of a light-sail powered by a radio beam generated on the surface of a planet.
Credit: PA)