Astronomers led by Northwestern University report that the James Webb Space Telescope (JWST) detects salty clouds in the atmosphere of an exoplanet informally known as the “Pink Planet.” The planet’s long-observed rosy haze has puzzled researchers for more than a decade, partly because the object is extremely faint and has been difficult to study in detail from Earth. In the new work, JWST provides improved observations of the planetary-mass companion, revealing atmospheric chemistry that includes unusual constituents. The researchers describe the presence of clouds composed of salt, which they say differ from clouds previously seen in other exoplanet atmospheres. The findings come as part of efforts to characterize the composition and properties of very cold, directly imaged planetary companions. While earlier observations could not resolve the atmosphere well enough to identify specific materials, the new JWST data allow scientists to infer more about the atmosphere’s composition, including the unexpected formation of salty cloud material.