Astronomers used the James Webb Space Telescope to study the atmosphere of WASP-94A b, a tidally locked gas giant 690 light-years away. The observations revealed cloudy mornings and clear evenings on the planet. The findings were published in Science.
A team led by Sagnick Mukherjee at Johns Hopkins University employed limb-resolved spectroscopy with JWST's NIRISS instrument. They split the transmission signals from the morning and evening limbs during the planet's transit, uncovering high-altitude aerosols on the morning side and water vapor on the evening side.