NASA Webb telescope observes daily cycle of rock clouds on hot Jupiter exoplanet WASP-94A b
A planet about 700 light-years away grows clouds of rock every morning and clears them by nightfall. NASA's James Webb telescope tracked the daily cycle on the hot Jupiter WASP-94A b, a rare direct view of weather shifting across a day on such a world. Source: NASA, ScienceDaily.
Roughly 700 light-years from Earth, a giant planet is doing something astronomers have rarely been able to watch happen on another world: changing its weather over the course of a day. The planet, WASP-94A b, is a hot Jupiter, a gas giant orbiting so close to its star that a full year lasts only a few days and surface temperatures soar high enough to vaporize rock. Using NASA's James Webb Space Telescope, scientists found that its mornings fill with clouds made of rock-like minerals, while by evening the skies turn surprisingly clear. The clouds form, drift, and vanish on a daily rhythm. What makes the observation notable is not just the strangeness of mineral clouds, but the fact that researchers could directly track them cycling across a single planetary day. Most exoplanet weather has to be inferred indirectly, so catching a cloud cycle in the act is a step forward for the field. Studying how clouds form and dissipate on extreme worlds like this one helps refine the models astronomers use to read the atmospheres of all exoplanets, including the smaller, cooler ones where the search for habitable conditions is focused. Source: NASA, ScienceDaily.