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Alien life in Universe: Scientists say finding it is 'only a matter of time'
Experts are optimistic of detecting life signs on a faraway world within our lifetimes - possibly in the next few years.
Science & Tech
Many astronomers are no longer asking whether there is life elsewhere in the Universe.
The question on their minds is instead: when will we find it?
Many are optimistic of detecting life signs on a faraway world within our lifetimes - possibly in the next few years.
And one scientist, leading a mission to Jupiter, goes as far as saying it would be "surprising" if there was no life on one of the planet's icy moons.
Nasa's James Webb Space Telescope (JWST) recently detected tantalising hints at life on a planet outside our Solar System - and it has many more worlds in its sights.
Numerous missions that are either underway or about to begin mark a new space race for the biggest scientific discovery of all time.
"We live in an infinite Universe, with infinite stars and planets. And it's been obvious to many of us that we can't be the only intelligent life out there," says Prof Catherine Heymans, Scotland's Astronomer Royal.
"We now have the technology and the capability to answer the question of whether we are alone in the cosmos."
The 'Goldilocks zone'
Telescopes can now analyse the atmospheres of planets orbiting distant stars, looking for chemicals that - on Earth at least - can be produced only by living organisms.
The first flicker of such a discovery came earlier this month. The possible sign of a gas that, on Earth, is produced by simple marine organisms was detected in the atmosphere of a planet named K2-18b, which is 120 light years away.
The planet is in what astronomers call ''the Goldilocks zone' - the right distance away from its star for the surface temperature to be neither too hot nor too cold, but just right for there to be liquid water, which is essential to support life.