NASA’S James Webb Space Telescope observed a planet outside of our galaxy that might be able to support life. Webb discovered the presence of methane and carbon dioxide on the exoplanet K2-18 b, which is 8.6 times the size of Earth. This indicates K2-18 b could be a Hycean exoplanet.
Exoplanets are planets beyond our solar system and Hycean, which comes from a combination of “hydrogen” and “ocean,” describes planets that scientists hypothesize have hydrogen-rich atmospheres and liquid-water oceans, according to Space.com.
There was also a possible detection of dimethyl sulfide, known as DMS, on K2-18 b. DMS is a molecule that, when on Earth, is produced by life, according to NASA.
K2-18 b is in the habitable zone, which means its distance from a star may allow water to exist on its surface. These zones are also known as “Goldilocks zones,” taking their name from the old children’s story because conditions are “just right” for life.
Not only did the planet show an abundance of methane and carbon dioxide, but also a shortage of ammonia. This means an ocean may exist under K2-18 b’s hydrogen-rich atmosphere, according to NASA.
The DMS on the planet also leads researchers to believe there could be life on the planet, since DMS in Earth’s atmosphere is created by phytoplankton, a marine algae that provides food to sea creatures and is created by sunlight.
“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, an astronomer at the University of Cambridge and lead author of the paper on these observations.
Planets like K2-18 b are still “poorly understood,” NASA says. However, some astronomers believe they could be a promising place to search for life.
“Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” Madhusudhan said. “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.”
The exoplanet’s oceans could be too hot to support life. But while K2-18 b has carbon-bearing molecules, it is not yet known if the planet could support life, according to NASA.
There have only been two observations of K2-18 b but there are “many more on the way,” said Savvas Constantinou of the University of Cambridge, who worked on the Webb team that observed the exoplanet. “This means our work here is but an early demonstration of what Webb can observe in habitable-zone exoplanets.”