Figure 1 from the 2014 paper confirming exoplanet’s existence.

Using the Webb Space Telescope’s infrared spectroscopic data astronomers believe they have detected the daily weather changes on exoplanet WASP-94A b, a hot gas giant about half the mass of Jupiter that orbits its star every four days.

Observations revealed that mornings and evenings on WASP-94A b have extremely different weather patterns: Mornings are riddled with clouds made of magnesium silicate, a common mineral found in rocks, while the evening has clear skies.

The star itself is about 700 light years away, and is known to have two exoplanets circling it.

The scientists proposed two explanations for their data. Either strong winds are clearing the air in the evening, or the clouds are the equivalent of morning fog on Earth that naturally dissipates as the day brightens.

Note that there is great uncertainty with these results, as we are only getting a very limited view from 700 light years away. In a sense, our knowledge of these exoplanets is comparable to what we knew of our own solar system’s planets prior to the space age. Once we got our first close looks at the planets almost everything we thought we knew beforehand turned out to be either wrong or misguided, due to the limited nature of the data.