Several dozen light years away from Earth, scientists have discovered an unusual exoplanet completely covered in water. However, this water world is far from what we see on Earth.
The ocean boils like a pot of water, with temperatures reaching 100 degrees Celsius and higher. The research results have been published in Astronomy and astrophysics.
Exoplanet TOI-270 d was discovered using NASA’s James Webb Space Telescope. Analysis of data obtained by the telescope showed that the atmosphere of TOI-270 d contains large amounts of methane and carbon dioxide, but no ammonia.
The absence of ammonia is an important indicator of the presence of an ocean on TOI-270 d. Chemistry shows that ammonia must be present in an atmosphere rich in hydrogen. But its ability to dissolve in water means there will be less of it in the atmosphere.
“This discovery is part of several JWST GO programs jointly carried out by NIRSpec, NIRISS and MIRI instruments,” said Professor Nikku Madhusudhan, who carried out the data analysis.
In addition to water, scientists also found signs of carbon disulfide in TOI-270 d’s atmosphere, which is linked to biological processes on Earth. However, the researchers emphasize that when assessing the possibility of the existence of life on TOI-270 d, one should not jump to conclusions.
“Further observations are needed to refine our understanding of the atmosphere and the likelihood of an ocean in TOI-270d,” said a scientist not involved in the study.
TOI-270 d is located about 70 light-years from Earth and has a striking temperature contrast. The planet is blocked by gravity: one side of it is constantly pointed towards its star and the other side is immersed in endless darkness. An extremely hot ocean has been discovered on the day side; More habitable conditions may exist on the night side.
“The ocean temperature can reach 100 degrees Celsius or more,” says Madhusudhan. “At high atmospheric pressure, such a hot ocean could still exist in a liquid state, although it is unclear whether it would be habitable.”
The discovery of TOI-270 d allows us to look at exoplanets in a different way and assess the habitability potential of such planets outside the Solar System. This is a great opportunity for scientists to study distant worlds that are very different from our own but could harbor life.
