Aliens are referred to as 'our sensitive topic' in the email – but neither man has been quiet about his interest in finding extraterrestrial life

'We should be wary of answering back'

It wouldn't be the first time that scientists have mistaken something earthly for something far more alien – last year it emerged that scientists had picked up interference from their microwave and thought it might have been sent from outer space

The star is gradually getting darker – and nobody knows why

Some have argued that it's only a matter of time till we find alien life – so we should get planning

But we shouldn't give up hope of finding extraterrestrials just yet

Professor Viren Swami found a 'signficant' link between high stress levels and stronger beliefs in conspiracy theories

The 'Wow!' signal has perplexed scientists for decades - but an explanation could be close

Hawking has warned humanity about our own barbarity, the growth of artifiical intelligence and the likelihood that any aliens we meet will want to kill us

Austrian weather forecasters Ubimet said there was no lightning in the area at the time that the video was apparently recorded

Many astronomers have presumed that planets in star clusters would have been thrown out into space — but they might actually have been perfect for supporting life, according to new research, because people could have travelled between planets much more easily

Monitoring of laser and radio signals from the star by astronomers haven't picked up any kind of unusual messages

A star identified by the Kepler Space Telescope may harbour structures which could point to an advanced technological civilisation

The FAST radio telescope will be the biggest and most sensitive ever constructed