Quite some time ago, astronomers have been keeping a close check on K2-18b. And now the possible aquatic world that revolves around a faint red star about 120 light-years distant just got a little bit more fascinating. The discoveries provide an enticing hint of dimethyl sulfide, which is a biological fingerprint that scientists think may be detectable on planets in the Hycean region.
There are many open questions, but this is only a first guess at this stage. The assumption is that if microbial aquatic life can form in these oceans in the same manner as they did on Earth, then some of the biosignatures may also be common, explained Nikku Madhusudhan, and astronomer at the University of Cambridge.
However, K2-18b is not at all like our own planet. It has an orbit around a red dwarf star that is rather near, occurring once every 33 days, and it weighs around 8.6 Earth masses and has a radius of approximately 2.6 Earth radii. In the year 2020, Madhusudhan and his team conducted an investigation of K2-18b and discovered that it may be habitable. In addition to that, they discovered that K2-18b might be a Hycean world in the year 2021. They used the near-infrared NIRSpec and NIRISS sensors on the JWST spacecraft to observe K2-18b as it made two orbits between our planet and its home star.
As a result, the researchers discovered traces of methane, carbon molecules, and carbon dioxide. The range of light also indicated some traces of dimethyl sulfide, but these traces were very faint.
The following stage will include directing the mid-infrared instrument known as MIRI on the James Webb Space Telescope (JWST) toward the exoplanet in order to conduct a more in-depth investigation into the likelihood of dimethyl sulfide and to search for other potential biosignatures in the atmosphere of the exoplanet.
The data are insufficient to conclude whether or not K2-18b is capable of supporting life as we know it. However, we are on the cusp of success.