Webb Telescope Maps Uranus’ Ionosphere in 3D
The European Space Agency reports that the James Webb Space Telescope used the Near-Infrared Spectrograph (NIRSpec) to study Uranus’ upper atmosphere, focusing on its ionosphere up to about 5,000 km above the clouds and creating a full-rotation 3D map to probe the planet’s magnetic field and auroras. The measurements show the hottest regions at roughly 3,000–4,000 km altitude with ion densities around 1,000 km, offering new insights into Uranus’ enigmatic magnetosphere and ice-giant atmospheres more broadly.
