A faraway planet in the constellation of Leo has been named the most habitable known world beyond the solar system after astronomers detected water vapour in its atmosphere.
It is the first time a planet in its star’s “Goldilocks zone” – where the temperature is neither too hot nor too cold for liquid water to exist – has been found to bear the life-sustaining substance in the blanket of gases that surround it.
The discovery has raised hopes that the planet, and similar worlds spotted in recent years, not only have conditions that can be suited to life, but in some cases may host living organisms.
“This is the first potentially habitable planet where the temperature is right and where we now know there is water,” said Angelos Tsiaras, an astronomer at University College London. “It’s the best candidate for habitability right now.”
The planet, named K2-18b, was first spotted in 2015 by Nasa’s Kepler space telescope. Roughly twice as big as Earth and eight times as massive, it orbits a cool red dwarf less than half the size of the sun, 110 light years away.