When you buy through links on our articles, Future and its syndication partners may earn a commission.Scientists say this high-resolution photo of the planet Mercury probably resembles the rocky exoplanet LHS 3844 b, which the JWST just observed. | Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of WashingtonAstronomers using the James Webb Space Telescope have, for the first time, directly analyzed the surface of a planet beyond our solar system,The James Webb Space Telescope’s (JWST) exoplanet subject, LHS 3844 b, is a so-called “super-Earth” about 30% larger than our planet and located nearly 50 light-years away. Unlike most exoplanet studies, which focus on atmospheres, astronomers analyzed heat emitted from this planet’s surface.AdvertisementAdvertisementThe findings reveal a dark, airless world that may resemble Mercury. Scientists say this kind of direct interpretation of a distant planet’s geology marks “the next step in unveiling their nature.””Thanks to the amazing sensitivity of JWST, we can detect light coming directly from the surface of this distant rocky planet,” Laura Kreidberg of the Max Planck Institute for Astronomy in Germany, who served as the principal investigator of the JWST observations, said in a statement. “We see a dark, hot, barren rock, devoid of any atmosphere.”Discovered in 2019, LHS 3844 b orbits a cool red dwarf star in just 11 hours and is tidally locked, meaning one side constantly faces the star while the other remains in darkness. The dayside reaches temperatures of about 1,340 degrees Fahrenheit (725 degrees Celsius), the scientists say.In 2023 and 2024, Kreidberg and her team observed three secondary eclipses, when the planet moved behind its star. Using the JWST’s Mid-Infrared Instrument (MIRI), they measured the infrared light emitted from the planet’s intensely hot dayside and used it to study its surface.AdvertisementAdvertisementBy comparing the signal with known rocks and minerals from Earth, the moon and Mars, the team ruled out an Earth-like crust rich in silica and granite. Such crusts typically form through water-driven geological processes and plate tectonics, which recycle rock and allow lighter minerals to rise to the …
