Astronomers have analysed the atmosphere of WASP-166 b, a hot super-Neptune exoplanet, revealing the presence of water and carbon dioxide. Using data from the James Webb Space Telescope (JWST), the observations also detected ammonia in smaller quantities. WASP-166 b is situated approximately 368 light-years away and is about seven times larger and 32 times heavier than Earth. The planet, orbiting its host star every 5.44 days at a distance of 0.067 AU, has an estimated equilibrium temperature of 1,270 K, placing it within the hot Neptune desert. Findings from JWST Observations As reported by phys.org, the JWST employed its Near Infrared Imager and Slitless Spectrograph (NIRISS) and Near Infrared Camera (NIRCam) to study WASP-166 b’s atmosphere. These observations highlighted water and carbon dioxide as dominant elements in the spectrum, alongside weak traces of ammonia and cloud deck pressure. Helium and hydrogen, in a primordial solar ratio, are believed to compose the remaining atmosphere. Searches for compounds like carbon monoxide yielded no significant results. Characteristics of WASP-166 and Its Planet WASP-166, the host star of this …