Michaela Leung: “Oxygen is currently difficult or impossible to detect on an Earth-like planet. However, methyl halides on Hycean worlds offer a unique opportunity for detection with existing technology.”
What can methyl halides, which are gases that consist of one carbon and three hydrogen atoms while being attached to a halogen atom, help scientists identify life beyond Earth? This is what a recent study published in The Astrophysical Journal Letters hopes to address as an international team of researchers investigated how methyl halides on exoplanets known as “Hycean” worlds could indicate the presence of life as we know it, or even as we don’t know it. Hycean exoplanets possess liquid water oceans with a hydrogen atmosphere above them, potentially enabling appropriate surface temperatures and pressures for life to exist.
For the study, the researchers discussed the potential for using NASA’s James Webb Space Telescope (JWST) to observe large exoplanets orbiting red dwarf stars, which are smaller and cooler than our Sun. The researchers noted that recent observations of K2-18 b and TOI-270 d, which are designated as Super-Earth and Neptune-like exoplanets, respectively, while each orbiting red dwarf stars. Additionally, such exoplanets could be ideal targets for JWST to identify methyl halides in their atmospheres. The reason Hycean exoplanets are considered ideal targets is due to the difficulty of observing Earth-sized exoplanets orbiting brighter stars.
