Astronomers have discovered that the exoplanet WASP-76b, located about 634 light-years away in the constellation Pisces, experiences extreme weather conditions unlike anything on Earth. With temperatures reaching about 4,350 degrees Fahrenheit (2,400 degrees Celsius), the planet’s atmosphere is buffeted by high-speed iron winds and molten metal rain. The findings highlight just how strange the atmospheres of exoplanets can be, especially on “hot Jupiters” like WASP-76b.
Unique atmospheric phenomena
The exoplanet’s proximity to its star makes it tidally locked, meaning that one side of WASP-76b is permanently facing the star. This day side reaches extreme temperatures that vaporize iron, which is then carried by powerful winds to the planet’s cooler night side. Once there, the iron condenses and falls as molten metal droplets, creating an intense and hostile environment.
The discovery was made by a team of scientists from the University of Geneva (UNIGE) and the PlanetS National Centre of Competence in Research (NCCR PlanetS), led by Ana Rita Costa Silva, a doctoral student at the Instituto de Astrofísica e Ciências do Espaço.
New insights into exoplanetary climates
Using the ESPRESSO instrument on the Very Large Telescope (VLT), the team was able to observe and measure the iron winds in the planet’s atmosphere. Christophe Lovis, an astronomer at UNIGE, noted that the precision of ESPRESSO allowed the team to gather detailed information about the dynamics of WASP-76b. The new findings helps scientists create 3D climate models, giving them a better understanding of the climate on planets outside our solar system.
In conclusion, WASP-76b continues to reveal extraordinary details about exoplanet atmospheres, providing valuable insights into the weather patterns on planets beyond our solar system. The discovery of iron winds and molten metal rain deepens our understanding of “hot Jupiter” planets, providing new perspectives on just how extreme planetary climates can be.
