Webb Telescope Maps Uranus's Upper Atmosphere in 3D
Astronomers have utilized the James Webb Space Telescope to create the first three-dimensional map of Uranus's upper atmosphere, revealing temperature peaks, ion density variations, and auroral structures influenced by the planet's unique magnetic field.
For the first time, astronomers have mapped the vertical structure of Uranus's upper atmosphere, uncovering how temperature and charged particles vary with altitude. Using the James Webb Space Telescope's NIRSpec instrument, the team observed Uranus for nearly a full rotation, detecting faint emissions from molecules high above the clouds.
The study, led by Paola Tiranti of Northumbria University, measured temperatures peaking between 3,000 and 4,000 kilometers above the planet, while ion densities peaked near 1,000 kilometers. These findings indicate that Uranus's upper atmosphere has been cooling over the past three decades.
Webb also detected two bright bands of auroral emission near Uranus's magnetic poles and identified a region with depleted emission and density, likely linked to the planet's unusually tilted and offset magnetic field.
Dr. Tiranti noted that this is the first time Uranus's upper atmosphere has been observed in three dimensions, allowing researchers to trace energy movement and the influence of its lopsided magnetic field.
These discoveries provide critical benchmarks for future missions and enhance understanding of how giant planets, both within our Solar System and beyond, balance energy in their upper atmospheres.