29 Cyg b is a massive companion to the star 29 Cygni, with a mass near the boundary between giant planets and brown dwarfs. Using the James Webb Space Telescope, astronomers directly imaged the planet and detected strong absorption from carbon monoxide and carbon dioxide in its atmosphere. The strength of the CO2 feature compared to CO indicates that 29 Cyg b is enriched in heavy elements, or metals, relative to its host star. This enhanced metallicity suggests that 29 Cyg b likely formed wit...