Webb Captures Dynamic Infrared Auroras on Jupiter

Jovian auroras shine hundreds of times brighter than those visible from Earth, according to a team of astronomers led by Dr. Jonathan Nichols at the University of Leicester.

When high-energy particles enter the planet’s atmosphere near its magnetic poles, they collide with gas atoms, creating the auroras.

Jupiter’s auroras are not only massive in scale but also exhibit energy levels hundreds of times greater than those seen on Earth.

These auroras are primarily triggered by solar storms, where charged particles entering the atmosphere excite gas particles, resulting in vibrant red, green, and purple hues.

Additionally, Jupiter has a unique source of auroral activity—its strong magnetic field captures charged particles from its surroundings.

This includes not only those from the solar wind but also particles ejected from the volcanic moon Io.

The eruptions from Io’s volcanoes release particles that escape both the moon’s and Jupiter’s gravitational pull.

Solar storms also discharge vast amounts of charged particles towards Jupiter.

Jupiter’s immense magnetic fields accelerate these charged particles to extraordinary speeds.

When these high-velocity particles collide with the planet’s atmosphere, they excite the gas and produce radiant displays.

https://www.youtube.com/watch?v=if0vpfergju

Thanks to the advanced capabilities of the NASA/ESA/CSA James Webb Space Telescope, new insights into Jovian auroras can be gained.

The telescope’s sensitivity enables astronomers to use faster shutter speeds to capture the rapidly evolving features of the auroras.

This latest data was collected using Webb’s near-infrared camera (NIRCAM) on Christmas Day 2023.

“What a Christmas gift; it truly astonished me!” exclaimed Dr. Nichols.

“We aimed to observe how quickly the aurora transformed, hoping to see beautiful fluctuations within about an hour.”

“Instead, we witnessed the entire aurora region illuminating the sky in a spectacular display.

Astronomers noted fluctuations in the effects caused by trihydrogen ions, known as H.³⁺, which varied more than previously assumed.

These observations help scientists unravel how Jupiter’s upper atmosphere undergoes heating and cooling.

Additionally, several unknown phenomena were identified in the data.

“What made these observations particularly intriguing was that the NASA/ESA Hubble Space Telescope was capturing images simultaneously in ultraviolet light,” Dr. Nichols commented.

“Strangely, the brightest light observed by Webb seemed to have no corresponding feature in Hubble’s images. This left me puzzled.”

“To produce the brightness observed in both Webb and Hubble, we would require an improbable mix of a substantial quantity of very low-energy particles impacting the atmosphere.

study Published in the journal Nature Communications.

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JD Nichols et al. 2025. The dynamic infrared aurora of Jupiter. Nature Communications 16, 3907; doi:10.1038/s41467-025-58984-z