The K2-18b Exoplanet Shows Signs of Harboring an Ocean, as James Webb Observations Confirm

The K2-18b Exoplanet Shows Signs of Harboring an Ocean, as James Webb Observations Confirm

If you think that the Pacific Ocean is large enough, how about finding a planet where its whole surface is covered by liquids? It could be the case of the K2-18b exoplanet, a so-called sub-Neptune located roughly 120 light-years away from us and into the Leo constellation.

The exoplanet in question has a size that places it somewhere between our planet and Neptune, as you’ve probably already guessed. By switching their focus on K2-18b while also using the powers of the James Webb Space Telescope (JWST), an international team of astronomers detected the presence of methane and carbon dioxide on the exoplanet, according to

Is the atmosphere of K2-18b rich in hydrogen?

The abundance of methane and carbon dioxide that exist on the K2-18b exoplanet makes astronomers suspect that there’s a hydrogen-rich atmosphere on the space object as well. They also believe that the entire surface of the exoplanet might be covered by a huge ocean.

K2-18b orbits a cool dwarf star dubbed as K2-18. The exoplanet was added to the long list of about 5,000 space objects that qualify as planets that exist elsewhere except our Solar System., which is the definition of the exoplanet itself.

Nikku Madhusudhan is the lead author of the paper that announces the new discovery ,and he’s also an astronomer at the University of Cambridge. He explained as quotes:

Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,

Traditionally, the search for life on exoplanets has focused primarily on smaller rocky planets, but the larger Hycean worlds are significantly more conducive to atmospheric observations.

It’s safe to assume that there is a chance, even if only theoretical, that the K2-18b exoplanet might host alien life. However, much more research is needed for astronomers to provide the right answer to that conundrum!


Even since he was a child, Cristian was staring curiously at the stars, wondering about the Universe and our place in it. Today he's seeing his dream come true by writing about the latest news in astronomy. Cristian is also glad to be covering health and other science topics, having significant experience in writing about such fields.

Post Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.