Astronomers reported possible signs of life at K2-18 b, a planet light-years away in the constellation Leo that could have a global ocean.
Nikku Madhusudhan, a University of Cambridge astrophysicist who leads the team, said his team’s progress was a “revolutionary moment.”
“A Hycean world with an ocean that is teeming with life is the scenario that best fits the data we have,” Madhusudhan said in a news release.
Astronomers have been using NASA’s James Webb Space Telescope to collect data from K2-18 b, a planet about 8 times bigger than Earth that was first discovered in 2015.
After the space telescope launched in 2021, Madhusudhan’s team reported in 2023 that there were signs of methane and carbon dioxide in the atmosphere of K2-18 b.
On Wednesday, in The Astrophysical Journal Letters, the team reported detecting dimethyl sulfide, or DMS, a chemical compound that could be a sign of life.
“This could be the tipping point, where suddenly the fundamental question of whether we’re alone in the universe is one we’re capable of answering,” Madhusudhan said.
Måns Holmberg, a researcher at the Space Telescope Science Institute in Baltimore who co-authored the report, said “it was an incredible” realization.
Savvas Constantinou, another co-author, viewed the announcement as a “starting point” for the investigations needed to confirm “the implications” of the “exciting findings.”
Not everyone in the scientific community celebrated the findings as progress in the search for proof of extraterrestrial life. Some argued that DMS isn’t a reliable biosignature, and more research is needed.
Madhusudhan welcomed the skepticism and said, “It’s only by testing and testing again that we will be able to reach the point where we’re confident ... That’s how science has to work.”