Stunning auroral activity has been observed on Jupiter, in an unexpected new discovery made possible by NASA’s James Webb Space Telescope (JWST) that has perplexed astronomers as to how it happens.
The auroras, revealed in unprecedented detail as they flicker across Jupiter’s poles, produce a dazzling light show that astronomers believe to be hundreds of times brighter than those that occur on Earth and far more dynamic than previously expected.
With the JWST’s advanced infrared sensitivity, new complexities about Jupiter’s powerful magnetosphere have been revealed, along with the giant planet’s intense auroras. The new findings were led by researchers at the University of Leicester.
Auroras on a Giant Scale
The new findings reveal the speed at which auroral emissions change on Jupiter, a discovery that challenges past assumptions and may potentially reshape the ways scientists understand the interactions that occur in the Jovian atmosphere and in the space surrounding it.
Of particular interest is the fact that due to the way that highly-charged particles collide with atoms and molecules in Jupiter’s atmosphere, its auroras are much larger and more intense than their earthly counterparts, which comprise the dancing colored displays known as the Northern and Southern Lights.
Powered by solar storms and volcanic activity occurring on the Jovian moon Io, eruptions from which eject significant amounts of charged particles into space around the gas giant, Jupiter’s powerful magnetic field captures the high-energy material these volcanoes produce, which ignites the planet’s auroras as they crash into Jupiter’s atmosphere.
The result is an auroral light show astronomers estimate to be hundreds of times brighter than anything seen over Earth’s poles.
A Holiday Surprise From Webb
The observations were first made on Christmas Day in 2023 by a research team led by Jonathan Nichols, which employed Webb’s Near-Infrared Camera (NIRCam) to observe Jupiter’s auroras. While Nichols and the team had anticipated slow, gradual changes in the planet’s polar glows, they were treated to a stunning holiday light show instead.
“What a Christmas present it was – it just blew me away!” Nichols said. “We wanted to see how quickly the auroras change… instead, we observed the whole auroral region fizzing and popping with light, sometimes varying by the second.”
In addition to Jupiter’s stunning “Christmas lights,” the team also focused part of their observations on the emission of trihydrogen cations (H₃⁺), particles commonly associated with auroral activity.
Through their observations, Nichols and his colleagues quickly discerned that the emissions they were seeing were far more variable than previous studies would have estimated, and provided insights into how Jupiter’s upper atmosphere warms up and cools down over time.
A Cosmic Mystery
Another exciting component of the team’s observations had been the puzzling discovery that simultaneous imagery collected by NASA’s Hubble Space Telescope did not reveal the same bright flashes at ultraviolet wavelengths that Webb’s NIRCam observed.
“What made these observations even more special is that we also took pictures simultaneously in the ultraviolet with NASA’s Hubble Space Telescope,” Nichols explained.
“Bizarrely, the brightest light observed by Webb had no real counterpart in Hubble’s pictures,” he added. “This has left us scratching our heads.”
“We still don’t understand how this happens,” Nichols said.
Astronomers say accounting for the observed light levels across the two telescopes would require large quantities of very low-energy particles, another discovery Nichols and the team hadn’t expected.
Going forward, the researchers hope that further observations of these anomalies will reveal new clues, perhaps with the help of data obtained by NASA’s Juno spacecraft, which is presently orbiting Jupiter.
This additional data, combined with future observations by Webb, could help to fundamentally reshape scientists’ understanding not only of what drives the auroral activity on Jupiter, but also may reveal clues about the broader dynamics of the planet’s magnetosphere and its relationship to its surrounding space environment.
The team’s study, “Dynamic infrared aurora on Jupiter,” was published in Nature Communications on May 12, 2025.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.