Astronomers discover a sizzling ocean planet, sparking curiosity about life beyond

Thanks to leaps in space technology, we're now scouting for life on distant planets beyond our Solar System. Recently, astronomers came across an exoplanet that seemed to be covered in an ocean similar to that of the Earth. As per the study done by astronomers of the University of Cambridge, the observations by Nasa’s James Webb space telescope (JWST) revealed prospectives of a "hycean" planet. While fascinating, the findings published in the Astronomy and Astrophysics Journal have sparked debate among astronomers, as per The Guardian. 

Known as TOI-270 d, this planet was twice the radius of Earth and nearly 70 light years away from us. The JWST observations showed the presence of water vapor and chemical signatures of methane and carbon dioxide in its atmosphere. Based on these data, the astronomers presumed the planet to have a deep water ocean underneath a hydrogen-based atmosphere. Lead researcher Professor Nikku Madhusudhan shared with media that the exoplanet's ocean temperatures could soar above 100 degrees Celsius. As per their study, "it’s not clear if the planet would be habitable," because of the extremely hot ocean water.

What gave away the presence of the ocean in the exoplanet was the absence of ammonia. Considering the fact that ammonia should naturally exist in a hydrogen-rich atmosphere, this lack of the chemical predicted a prospect of the ocean. With the ocean water dissolving the ammonia, the atmosphere seemed to be devoid of it, as per the research. Madhusudhan explained, "One interpretation is that this is a so-called ‘hycean’ world – with a water ocean under a hydrogen-rich atmosphere." As per Britannica, a Hycean world is a mini-Neptune constituting majorly of watery ocean surrounded by a hydrogen-helium atmosphere. However, in the case of TOI-270 d, the oceans are not similar to that of Earth as the exoplanet faces its star on one side permanently with the other side swaddled by endless darkness.

So, based on these contrasting temperature conditions, Madhusudhan said, "The ocean would be extremely hot on the day side. The night side could potentially host habitable conditions." But one cannot ignore the extreme atmospheric conditions that have tens or hundreds of times the pressure at the Earth’s surface. The waters may run to immeasurable kilometers of depth in the ocean with steam rolling off on its surface. Disputing this "hycean" hypothesis, Prof Björn Benneke, of the University of Montreal who examined the same exoplanet's data, told the media, "The temperature in our view is too warm for water to be liquid." As per Benneke, with the possibility of temperature reaching up to 4000C, the water would be existing, "almost like a thick, hot fluid." 

However, both teams of astronomers unanimously agreed with the presence of carbon disulfide - a compound associated with biological processes on Earth. Researchers caution against jumping to conclusions about the exoplanet's habitability based on this compound's presence. "We need to be extremely careful about how we communicate findings on this kind of object. It’s easy for the public to jump on to the idea that we’re finding life already," Madhusudhan said. Researchers look forward to the possibility of measuring unique molecules to deduce more about habitable planets in the future.