Washington, Sept. 12, (dpa/GNA) – Scientists at US space agency NASA have discovered an exoplanet with the potential for a hydrogen-rich atmosphere and a water ocean-covered surface.
K2-18 b, an exoplanet 8.6 times as massive as Earth, was examined with the help of the James Webb space telescope.
The presence of carbon-bearing molecules including methane and carbon dioxide was “intriguing,” as some astronomers believed that these worlds are “promising environments to search for evidence for life,” NASA said on Monday.
“Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” astronomer at the University of Cambridge and lead author of the paper announcing the findings Nikku Madhusudhan said.
The abundance of methane and carbon dioxide, and shortage of ammonia, supported the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b.
There was also a possible detection of a molecule called dimethyl sulfide (DMS) but more research is needed, NASA said. On Earth, DMS is only produced by life, with the bulk of the molecule emitted from phytoplankton in marine environments.
While K2-18 b lies in the habitable zone, and harboured carbon-bearing molecules, this did not necessarily mean it could support life, NASA added.
The planet’s size suggested it contained a large mantle of high-pressure ice, like Neptune, but with a thinner hydrogen-rich atmosphere and an ocean surface. It was also possible that the ocean was too hot to be habitable or be liquid.
Scientist will conduct further research into the environmental conditions on K2-18 b.
“Our ultimate goal is the identification of life on a habitable exoplanet, which would transform our understanding of our place in the universe,” Madhusudhan said. “Our findings are a promising step towards a deeper understanding of Hycean worlds in this quest.”
GNA