NASA have put out a press release about observations of hot-Jupiter exoplanet WASP-121b. A team led by ESA scientist Quentin Changeat analysed observations with the Hubble Space Telescope made in 2016, 2018 and 2019 to find distinct differences in the atmosphere of the planet, revealing that planets have weather patterns.

The figure below shows the “phase curve”, a smooth variation caused by the varying visibility of the heated face of the planet (there are also sharp dips caused by the eclipse and transit of the star/planet). Differences between the phase curve in different years indicate changes in the atmosphere.

Heat maps of WASP-121b show the changing temperatures of the irradiated face of WASP-121b.

The press release has led to articles on WASP-121b on dozens of websites across the world.