An article published in the journal “Nature” reports the results of an examination of the exoplanet WASP-18b. A team of researchers used the James Webb Space Telescope to map the temperatures on the surface of this ultra-hot Jupiter very close to its star. The temperature variations are around 1,000° Kelvin between the hottest area always facing its star and the border area between day and night. Webb’s Near-Infrared Imager and Slitless Spectrograph (NIRISS) also found traces of water vapor that other instruments had missed.