Don’t pack your bags for the trip to exoplanet K2-18b quite yet — it turns out that the James Webb Space Telescope may not have detected signs of life there after all. Last year, astronomers reported the possible presence of dimethyl sulfide there, a gas that (at least on Earth) is generally associated with phytoplankton in the ocean. Webb used its infrared spectrometer instruments to look at the light from the planet’s star, a red dwarf about 111 light-years away, as it passed through the hydrogen-rich atmosphere. The finding was sort of incidental to the discovery of much stronger signals for methane and carbon dioxide, but it turns out that the DMS signal might have just been overlap from the methane signal. It’s too bad, because K2-18b seems to be somewhat Earth-like, if you can get over the lack of oxygen and the average temperature just below freezing. So, maybe not a great place to visit, but it would be nice to see if life, uh, found a way anywhere else in the universe.
This is a companion discussion topic for the original entry at https://hackaday.com/2024/05/12/hackaday-links-may-12-2024/