NASA’s James Webb Space Telescope has done it again. Researchers at the University of Cambridge have observed a distant planet that could be completely covered by a deep-sea ocean. Evidence for TOI-270’s ocean is based on the absence of ammonia, which basic chemistry predicts should occur naturally in a hydrogen-rich atmosphere.
JWST evealed water vapor and chemical signatures of methane and carbon dioxide in the atmosphere of the exoplanet
The observations, made by NASA’s James Webb Space Telescope (JWST), revealed water vapor and chemical signatures of methane and carbon dioxide in the atmosphere of the exoplanet, which is twice the radius of Earth and about 70 light-years away. The oceans, which cover more than 71% of the Earth’s surface and contain 97% of the planet’s water, are a major factor in the global climate. “The ocean could be around 100 degrees Celsius,” said Professor Nikku Madhusudhan, who led the study. They not only act as temperature control systems, but also contribute to the water cycle by releasing water vapor into the atmosphere.
It’s also important to pause for a moment on this point, as while there are studies that suggest the presence of water, other experts disagree. This interpretation is supported by an article published in the journal Astronomy and Astrophysics Letters , but is challenged by a Canadian team that made additional observations of the same exoplanet, known as TOI-270 d.
The abundance of methane and carbon dioxide, and shortage of ammonia, supports the hypothesis that there may be a water ocean
And we add more information. In a study published in 2023, similar sediments were already found. A new investigation with NASA’s James Webb Space Telescope into K2-18 b has revealed the presence of carbon-bearing molecules including methane and carbon dioxide. The abundance of methane and carbon dioxide, and shortage of ammonia, supports the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b.
The suggestion that the sub-Neptune K2-18 b could be a Hycean exoplanet is intriguing, as some astronomers believe that these worlds are promising environments to search for evidence for life on exoplanets, according to the study published on the NASA website. “Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” explained Nikku Madhusudhan and adds: “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 telescope captures starlight that has filtered through the atmospheres of orbiting planets to provide detailed breakdowns
In any case, these latest observations demonstrate the surprising insights James Webb is providing into the nature of planets beyond our solar system. The telescope captures starlight that has filtered through the atmospheres of orbiting planets to provide detailed breakdowns of the chemical elements present. The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b.
“Our findings are a promising step towards a deeper understanding of Hycean worlds in this quest”
From James Webb observations, astronomers can gain insight into the conditions on a planet’s surface and the likelihood of life surviving there. These initial Webb observations also provided a possible detection of a molecule called dimethyl sulfide (DMS). On Earth, this is only produced by life. The bulk of DMS in Earth’s atmosphere is emitted from phytoplankton in marine environments.
Finally, regarding temperature, which is the most debated issue among experts, Madhusudhan says that “the ocean would be extremely warm during the day, but the night side could potentially harbor habitable conditions.” In any case, the researcher concludes by saying that: “Our findings are a promising step towards a deeper understanding of Hycean worlds in this quest.”
