Astronomers have made a remarkable discovery about the exoplanet WASP-76blocated about 634 light-years away in the Pisces constellationwhich experiences incredibly harsh weather conditions unlike any seen on Earth. The planet, classified as a “hot Jupiter“endures searing temperatures of around 4,350°F (2,400°C)leading to extreme atmospheric phenomena, including iron winds and molten metal rain.
Due to its close orbit around its star, WASP-76b is tidally lockedmeaning one side of the planet always faces the star, subjecting it to constant heat. This side becomes so hot that iron in the atmosphere is vaporized. Powerful winds carry this vapor to the planet’s cooler nightsidewhere the iron cools and condenses into droplets, resulting in metallic rain.
This discovery, led by a team of scientists from the University of Geneva (UNIGE) and the NCCR PlanetSwas made using the ESPRESSO instrument on the Very Large Telescope (VLT). Ana Rita Costa Silva, a doctoral student at the Instituto de Astrofísica e Ciências do Espaço, and her team observed the iron winds in the planet’s atmosphere, offering unprecedented insights into the planet’s dynamic climate.
Christophe Lovis, an astronomer from UNIGE, highlighted the precision of the ESPRESSO instrument, which allowed the team to collect detailed data on WASP-76b’s atmospheric processes. These observations will help scientists build 3D climate modelsoffering valuable knowledge about the weather patterns and climates on exoplanets far beyond our solar system.
In summary, the discovery of iron winds and molten metal rain on WASP-76b expands our understanding of the extreme conditions on hot Jupiter exoplanets and reveals the incredible diversity of planetary atmospheres in the universe.
