NASA says exoplanet K2-18 b could be an ocean world, or a “Hycean” planet.

Astronomers, led by the University of Cambridge, found methane and carbon dioxide in the atmosphere of K2-18 b, findings that are “consistent with an ocean-covered surface under a hydrogen-rich atmosphere,” the university said. He said.

“This discovery offers a glimpse of a planet unlike anything else in our solar system, and raises intriguing prospects about potentially habitable worlds elsewhere in the universe,” she said on Monday.

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NASA He said The findings – including “an abundance of methane and carbon dioxide, and a lack of ammonia” – support the hypothesis that the exoplanet may be covered by an ocean.

The researchers said they also detected “another weaker signal” that could point to the molecule called dimethyl sulfide, raising the possibility of biological activity on K2-18 b. On Earth, this molecule is only produced by life, emitted by phytoplankton in marine environments, NASA said He says.

But the DMS discovery has not yet been confirmed, and the team will follow up with further observations from NASA’s Webb telescope. He added.

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The astronomers note that their findings don’t necessarily mean the planet could support life: its large size means its interior could contain a large cap of high-pressure ice, like Neptune’s, but with a thinner hydrogen-rich atmosphere and an oceanic surface. This planet could support life. He said. The ocean may be too hot to live in.

This is not the first time that astronomers have seen signs of water on other planets. Evidence of water vapor was previously found on one of the rocks Exoplanet It is approximately the size of the planet Neptune, and is about 120 light-years away from us.

However, they described the new discoveries as a gateway to more knowledge about extraterrestrial planets.

NASA said the possibility that K2-18 b could be a Hycean exoplanet, or ocean world, was “interesting,” as some astronomers believe such planets are promising environments to search for evidence of life on exoplanets.

“Our findings underscore the importance of considering diverse habitable environments when searching for life elsewhere,” said astrophysicist Niku Madhusudan of the Cambridge Institute of Astronomy, lead author of the study.

K2-18 b, which is more than twice the size of Earth, was discovered in 2015 and is located in its star’s “habitable zone,” a region that is neither too hot nor too cold to contain liquid water.

The first insight into the properties of the planet’s atmosphere came NASA’s Hubble Space TelescopeThe technology of its successor, the Webb telescope, including its extended wavelength range and “unprecedented sensitivity,” made the recent discoveries possible, Madhusudan said.

The $10 billion Webb Telescope has delved into space and provided new observations of distant galaxies since its launch in December 2021.

“These results are the result of just two observations of K2-18 b, and there are more on the way,” said co-author and researcher Savvas Constantinou from the University of Cambridge.