The search for alien life should broaden its horizons a bit, a new study suggests.
Alien hunters have to date focused largely on Earthlike planets — a reasonable place to start, given that our rocky, water-covered world is the only one we know of that hosts life. But the universe teems with a huge diversity of planets, some of which may be habitable despite being decidedly un-Earthlike.
In the new study, researchers identify one such class of alien worlds — “Hycean” planets, which are up to 2.5 times larger than Earth and feature huge oceans of liquid water beneath hydrogen-rich atmospheres. Hycean planets appear to be incredibly abundant throughout the Milky Way galaxy, and they could host microbial life similar to the “extremophiles” that thrive in some of Earth’s harshest environments, study team members said.
“Hycean planets open a whole new avenue in our search for life elsewhere,” lead author Nikku Madhusudhan, of the Institute of Astronomy at the University of Cambridge in England, said in a statement.