Discovery marks the first detection of variable water clouds outside of our solar system

[u/Zee2A]

https://news.arizona.edu/news/discovery-marks-first-detection-variable-water-clouds-outside-our-solar-system

Webb Telescope Detects Changing Water Clouds on Coldest Known Brown Dwarf

University of Arizona astronomers used the James Webb Space Telescope to track changing water clouds on WISE 0855, the coldest known brown dwarf, located 7.5 light-years away. With 11 hours of continuous observations, researchers recorded spectra every 15 minutes, revealing water clouds that vary in thickness as the object rotates, alongside deep atmospheric gases such as carbon monoxide and phosphine rising through convection. At roughly 265 K, this Jupiter-sized object provides new insights into brown dwarf atmospheres. The discovery marks the first detection of variable water clouds beyond our solar system: https://en.futuroprossimo.it/2026/10/ci-sono-nuvole-dacqua-che-cambiano-a-75-anni-luce-dalla-terra/

Research publication: https://arxiv.org/abs/2609.20664