James Webb Space Telescope Reveals 3D Map of Uranus’s Atmosphere

An international research team published the first three-dimensional map of Uranus’s upper atmosphere and ionosphere in February 2026, using data from the James Webb Space Telescope. The findings provide new insights into the planet’s atmospheric structure and magnetic environment.

The research team used the James Webb Space Telescope’s Near-Infrared Spectrograph to observe Uranus continuously for 15 hours on January 19, 2025. This observation period captured nearly a complete rotation of the planet, enabling detailed mapping of its atmospheric features.

The resulting 3D map revealed two prominent auroral bands near Uranus’s magnetic poles. Between these bands, scientists identified a region with lower emission and ion density, which likely corresponds to transitions in the planet’s magnetic field lines.

Uranus’s magnetic field is both tilted and offset from its rotation axis, creating complex auroral patterns that sweep across the planet. The study also found that longitudinal differences in ion density and temperature align with the geometry of the magnetic field, indicating uneven distribution of energy and particles in the upper atmosphere.

What the numbers show

• Observations were made over 15 hours on January 19, 2025
• Average thermospheric temperature measured at about 426 kelvins (150 °C
• Ion density peaks around 1,000 km above the cloud tops; temperature peaks between 3,000 and 4,000 km altitude

The study measured an average temperature of approximately 426 kelvins in Uranus’s thermosphere, which is lower than previous estimates from ground-based telescopes and earlier spacecraft. This temperature finding extends a cooling trend in the planet’s upper atmosphere that has been observed since the early 1990s.

The mapping results were published in the journal Geophysical Research Letters. The data provide a new reference for understanding the atmospheric and magnetic characteristics of Uranus, which had not previously been mapped in three dimensions.

The 3D mapping approach used in this study offers a method for characterizing the upper atmospheres and ionospheres of other giant planets beyond the solar system. Researchers stated that this template could support future comparative studies of exoplanetary atmospheres.

By capturing nearly a full rotation of Uranus and providing detailed altitude profiles, the observations from the James Webb Space Telescope have contributed to a better understanding of the planet’s atmospheric dynamics and magnetic field structure.

* This article is based on publicly available information at the time of writing.