For over a decade, the Pink Planet—one of the coldest and faintest directly imaged planetary-mass companions—kept its secrets hidden from Earth-based telescopes. Now, new observations from the James Webb Space Telescope have cracked the case, revealing an atmosphere unlike any seen before.
Led by Northwestern University, the team discovered that the ancient, rosy-hazed world hosts skies filled with exotic chemistry. The standout finding: salty clouds, a surprise that reshapes understanding of such cold, directly imaged objects.
The object's faintness had long frustrated astronomers trying to dissect its light. JWST's infrared capabilities finally pierced the haze, delivering data on chemical compounds and cloud composition that ground-based instruments simply couldn't capture.
These salty skies hint at dynamic atmospheric processes previously unobserved on planetary-mass companions. The discovery opens new questions about how such worlds form and evolve, especially at extreme temperatures where exotic chemistry dominates.
The findings challenge existing models of cold atmosphere chemistry, suggesting that salts may play a larger role than assumed. Future JWST observations could target similar faint worlds to see if this pattern holds.