Exoplanet's surface may be covered in oceans, James Webb Space Telescope finds

[Takket]

2. the planet also contains a (still to be confirmed) molecule only associated with life on Earth

https://www.theguardian.com/science/2023/sep/11/nasa-planet-ocean-life-james-webb-telescope

The space agency said that its observations of the chemical makeup of the planet’s atmosphere suggested the possibility of an ocean world. “The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b,” it said.

But the agency also hinted at even more remarkable possibility in the potential finding of a molecule called dimethyl sulfide (DMS), which on Earth is only produced by life.

“The bulk of the DMS in Earth’s atmosphere is emitted from phytoplankton in marine environments,” the Nasa press release said.

The presence of DMS, however, is still to be confirmed, and requires further investigation. “Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2-18 b at significant levels,” said Nikku Madhusudhan, a University of Cambridge astronomer and lead author of the Nasa research.