A team at the Institute for Research on Exoplanets at the Université de Montréal published their findings yesterday. Led by Björn Benneke, their work (which has not been peer reviewed) points to the possibility that K2-18 b is habitat thanks to the availability of water and hydrogen, as well as the location of the exoplanet in the Goldilocks zone. The Goldilocks zone is a column related to a star where the temperature is neither too hot nor too cold to support life. But while the temperature range and availability of water are good signs, K2-18 b is not necessarily residential. The exoplanet is not a giant gas, but it has a thick, high-pressure environment likely to be contained in a large, rocky core. Because of the crushing pressure, humans cannot walk on the planet; this is more of a Cloud City scenario, with pods floating in an over-gas environment. The planet may have rain clouds – though researchers have not confirmed it yet. As the water leaks into the liquid, drops drop to the core, then back to the gas as atmospheric pressure increases. The gas will rise to the cloud layer and repeat the cycle.
Benneke and his fellow researchers will follow their work in the 2020s, after launching the James Webb Space Telescope in 2021. The new telescope is much stronger than the Hubble Space Telescope, which the team used to study K2-18 b because it passed in front of its star. A more detailed look through the James Webb Space Telescope will help confirm the presence of rain on the planet, and will allow researchers to find more planets like Earth.
Each passing decade has led to a discovery that changes the way we think about our universe: Dark energy was confirmed in the 2000s and in 2010 saw the first real confirmation of a black hole. 2020 may be the decade when we find out that the Earth, with its dry land and liquid oceans, is not as unique as we currently believe.