It’s looking increasingly less likely that we’re alone in the universe, as astronomers at the University of Cambridge have discovered a whole new class of habitable exoplanets. Dubbed ‘hycean’ planets, they’re more than twice the radius of Earth and have around ten times the mass.
Scientists had previously focused on finding ‘Earth twins’ with similar atmospheres to our planet which could support alien life, but they believe these new exoplanets seem to be a more promising way of locating new life forms.
In comparison to our planet, hyceans are a lot more watery – and hot. The ocean-covered planets have hydrogen-rich atmospheres, with the water layer accounting for 90 per cent of the planet’s mass, and average temperatures reaching almost 200℃. Some orbit so close to their stars that they’re tidally locked, with one scorching-hot dayside and one eternally dark nightside. Sounds nice!
Cambridge’s researchers say the findings could mean that discovering signs of life outside our Solar System within the next few years is a real possibility. “Hycean planets open a whole new avenue in our search for life elsewhere,” said the study’s lead author, Nikku Madhusudhan. “We are saying that within two to three years we may see the first biosignature detection if these planets host life.”
Discovering signs of life – past or present – “would transform our understanding of life in the universe”, Madhusudhan added. “We need to be open about where we expect to find life and what form that life could take, as nature continues to surprise us in often unimaginable ways.”
The atmospheres will be examined by NASA’s $9.8 billion (£7.1bn) James Webb Space Telescope, which will be able to look back in time to just a few hundred million years after the Big Bang, and is scheduled to launch later this year.