JWST data reveal silicate clouds and high metallicity in WASP-107 b’s atmosphere

Star system: WASP 107 | Distance from the Sun: 210 light years

WASP-107 b is a warm gas giant planet that has been studied in detail using the James Webb Space Telescope (JWST). Its atmosphere shows a unique feature at 8–10 micrometers, thought to be caused by silicate clouds. Scientists aimed to explain the planet’s full spectrum, from near-infrared to mid-infrared, using a physically realistic model of cloud formation and temperature.

The research team used a model that links how clouds form with how heat moves through the atmosphere. They found that both the silicate cloud feature and the strengths of water and carbon dioxide bands can be explained if turbulence in the atmosphere lifts cloud particles high above the planet. The best fit to the data suggests WASP-107 b’s atmosphere is about 17 times richer in heavy elements than the Sun. This study shows that even on warm planets, silicate clouds can form in the upper atmosphere if there is enough turbulence, and that a self-consistent model can match the observed data well.

Key findings
- WASP-107 b’s atmosphere contains silicate clouds, revealed by a feature at 10 micrometers
- Turbulence with a vertical diffusivity of Kzz = 10^9 cm^2 s^-1 is needed to lift cloud particles
- The atmosphere’s metallicity is about 17 times that of the Sun
- Both water and carbon dioxide bands are well explained by the model
- Self-consistent modeling fits the planet’s spectrum without extra assumptions

Scientific study

A Cloudy Fit to the Atmosphere of WASP-107 b (external link)