James Webb Telescope detects water clouds on brown dwarf WISE 0855-0714

The James Webb Space Telescope (JWST) has identified definitive evidence of water clouds on WISE 0855-0714, a brown dwarf located approximately 7.5 light-years from Earth in the constellation Hydra.

WISE 0855-0714, often referred to as a “failed star,” sits on the boundary between a giant gas planet and a brown dwarf. It possesses a mass roughly five times that of Jupiter and maintains extremely low temperatures, described as a “cosmic refrigerator.”

Researchers from the University of Arizona’s Steward Observatory used the JWST to track the object for an 11-hour window, collecting data at 15-minute intervals. This granular observation allowed scientists to distinguish between the effects of clouds, chemistry, and temperature. The data revealed that water vapor formations in the upper atmosphere actively fluctuate in thickness as the object rotates, creating dynamic weather systems similar to those seen on Jupiter.