A pair of scorched worlds circling the red dwarf TRAPPIST-1 now offer one of the clearest looks yet at what life may be up against around the most common stars in the Milky Way. Using the James Webb Space Telescope, an international team that included researchers from the University of Bern and the University of Geneva has, for the first time, mapped the climate of rocky exoplanets with masses similar to Earth. Their target was not a giant gas planet or a bloated world with an easy-to-read atmosphere, but two small rocky planets in the famous TRAPPIST-1 system, known as TRAPPIST-1b and TRAPPIST-1c. What they found was stark. The two worlds seem to swing between blistering daylight and brutal cold, with day-to-night temperature differences topping 500 degrees Celsius. That kind of contrast points to a simple conclusion: neither planet appears to have a dense atmosphere capable of moving heat from one side to the other. The result, published in Nature Astronomy, sharpens one of the biggest questions in exoplanet science. Rocky planets around red dwarf …