In 2019, two independent scientific studies combining data from the Kepler, Spitzer and Hubble space telescopes concluded that significant amounts of water vapor exist in the atmosphere of K2-18 b. This was discovered for the first time for an exoplanet located in the habitable zone[8][10][11]. In 2023, the planet was observed by the James Webb telescope. In its atmosphere, molecules of methane and carbon dioxide were found, as well as signs of the possible presence of dimethyl sulfide, which may indicate the existence of life in a hypothetical ocean on its surface [12] [13]. On Earth, dimethyl sulfide is produced in any noticeable quantities only by living organisms, but NASA emphasized that the conclusion about the presence of dimethyl sulfide in the atmosphere of an exoplanet is preliminary and requires further confirmation. Although K2-18 b is in the habitable zone and contains carbon-containing molecules, this does not necessarily mean that it is suitable for life. The planet's large size—2.6 times the size of Earth—means the planet likely has a mantle of high-pressure "ice" like Neptune, but a thinner hydrogen-rich atmosphere and ocean. However, the ocean may be too hot to be habitable or liquid[14].