The Daily Mail has reported that renowned astrophysicist, Stephen Hawking, has revealed that he strongly believes in aliens and warned that Earth could be at risk from an invasion.

In a documentary series for the Discovery Channel, the eminent scientist argued that it is “perfectly rational” to assume intelligent life exists elsewhere in the universe. And in an extraordinary series of assertions, he said Earth might be at risk from what he imagines to be “massive ships” which could try to colonize our planet and plunder our resources. According to Hawking:

“We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet. I imagine they might exist in massive ships, having used up all the resources from their home planet. Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they can reach.”

The renowned 68-year-old scientist has spent three years working on the documentary series, despite being paralyzed by motor neuron disease. Hawking said that most ALIEN LIFE is likely to consist of small animals or microbes in planets, stars or floating in space, but the existence of 100 billion galaxies each containing hundreds of millions of stars means Earth is unlikely to be the only place where life has evolved:

“To my mathematical brain, the numbers alone make thinking about aliens perfectly rational. The real challenge is to work out what aliens might actually be like.”

Hawking has in the past suggested a more open-minded attitude toward extraterrestrials, but the discovery of more than 450 previously-unknown planets orbiting distant stars since 1995 is believed to have strengthened his belief.

Britain’s leading astronomer, Lord Rees of the Astronomer Royal and president of the Royal Society, also provoked controversy by saying that the chance of detecting alien life was stronger than ever before:

“I suspect there could be life and intelligence out there in forms that we can’t conceive… and there could, of course, be forms of intelligence beyond human capacity, beyond as much as we are beyond a chimpanzee.”

Bur Professor Hawking adds a cautionary note to anyone to eager to encounter a species more advanced than our own:

“If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn’t turn out very well for the Native Americans.”

Stephen Hawking’s Universe begins on the Discovery Channel on Sunday May 9 at 9pm.