The truth about life on other planets – and what it means for humans

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There are some scientific discoveries that do much more than advance our knowledge: they create a shift in our psyche as they show us the scale of the Universe and our place in it.

One such moment was when space craft sent back images of the Earth for the first time. Another is the discovery of life on another world, a moment that has inched a little closer today with the news that signs of a gas, which on Earth is produced by simple marine organisms, has been found on a planet called K2-18b.

Now, the prospect of really finding alien life – meaning we are not alone in the Universe – is not far away, according to the scientist leading the team that made the detection.

“This is basically as big as it gets in terms of fundamental questions, and we may be on the verge of answering that question,” says Prof Nikku Madhusudhan of the Institute of Astronomy at Cambridge University.

But all of this prompts even more questions, including, if they do find life on another world, how will this change us as a species?

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