James Webb Telescope studied the weather of the coldest brown dwarf

According to Ixbt.com, an international team of astronomers has for the first time created a detailed weather map of the coldest known brown dwarf, WISE 0855. With a temperature of just 265 Kelvin, this star-like object is colder than any planet in our Solar System and is significant for being at the transition boundary between stars and massive gas giants. This is reported by Ixbt.com reports .

Using the NIRSpec spectrograph on the James Webb Space Telescope, one of the most powerful instruments in space, scientists observed this mysterious object continuously for 11 hours. The analysis showed that despite the freezing external environment, the atmosphere of WISE 0855 is complex and turbulent, covered in water clouds and remnants of carbon monoxide.

The secret of molecular changes in the atmosphere

During the study, James Webb separated the radiation into individual components, clearly showing how each molecule pulsates. Carbon monoxide showed the primary dynamics, with its light fluctuations reaching 10 percent from peak to trough. Phosphine also showed unique activity, proving that the behavior of both gases is controlled by a single mechanism deep within the atmosphere.

However, methane, ammonia, and water vapor showed very weak variability in their maximum opacity zones. To explain the results, scientists turned to two atmospheric models called PICASO and coolTLUSTY. It turns out that the observed processes can only be fully understood if the object's temperature and cloud thickness change simultaneously.

Strong winds and future observations

The outer layers of WISE 0855 are covered with water clouds that change thickness during rotation. At the same time, gases rising from deep layers cause unexpected differences in vertical movement. Experts believe that the object does not have stable vortices like Jupiter's Great Red Spot, but rather intense equatorial and mid-latitude jets.

Currently, the exact rotation period of the object has not been fully established, and the data indicate complex dynamics associated with multi-component winds. This discovery serves as an important scientific bridge between studying the weather of gas giants like Jupiter and Saturn and future research on Earth-like exoplanets.