Salt Clouds Redefine the Pink Planet’s Cold Atmosphere

Astronomers using the James Webb Space Telescope have detected salt clouds in the atmosphere of the cold exoplanet GJ 504 b (the Pink Planet), explaining its spectral signature and prompting revised models of cloud chemistry for distant, frigid worlds; the planet, about 57 light-years away and first discovered in 2013, shows a mix of water vapor, methane, carbon dioxide and ammonia that only fits when salty clouds are included in atmospheric simulations.