Jupiter’s Lightning May Dwarf Earth’s by a Millionfold
How powerful does a storm have to be before Earth’s lightning starts to look ordinary? New analysis of Jupiter’s atmosphere is sharpening that comparison in a dramatic way. Researchers studying radio signals from the giant planet’s storms found that many Jovian lightning flashes span a broad range, from roughly Earth-like discharges to bolts more than 100 times stronger. Because of unresolved differences in how the two planets’ signals were measured, the upper end may be even more extreme, with some estimates reaching up to a million times stronger than terrestrial lightning.
The result matters for more than spectacle. Lightning acts as a tracer of deep atmospheric convection, revealing where heat, moisture, and vertical motion are doing the hidden work of building storms. On Jupiter, where tempests can persist for months or far longer, that makes every flash a clue to how the solar system’s largest atmosphere moves energy from below the cloud tops to the heights above them.
For years, much of what scientists knew came from nightside images that naturally favored the brightest events. That created a skewed picture, making Jupiter’s bolts seem comparable mainly to Earth’s rare “superbolts.” The view changed after Juno arrived in orbit in 2016. Its instruments began detecting fainter activity that suggested Jupiter was not producing one uniform class of lightning, but something more varied and physically revealing. The obstacle was that visible-light observations can be distorted by thick clouds, and Jupiter’s banded atmosphere often hosts several storms at once, making it hard to tell which storm generated which flash. The breakthrough came during a calm period along the North Equatorial Belt in 2021 and 2022, when isolated storms stood out clearly enough to be tracked with Juno, Hubble, and amateur observations.
Michael Wong of the University of California, Berkeley, described the payoff directly: It was so gratifying to work through the statistics and see that with our Juno data, we were really capturing the majority of lightning pulses at radio wavelengths. The team focused on four so-called stealth superstorms, unusually persistent systems that lasted for months even though their cloud towers were less conspicuous than Jupiter’s most famous convective outbursts. By using Juno’s microwave and radio instruments instead of relying only on visible flashes, researchers could study lightning that clouds would otherwise hide. Across 613 measured pulses, the spacecraft recorded an average rate of about three flashes per second during close passes.
The deeper puzzle is why Jupiter can energize lightning so efficiently. On Earth, moist air rises relatively easily through a nitrogen-rich atmosphere. On Jupiter, the atmosphere is dominated by hydrogen, and the physics of buoyancy works differently: moist parcels are harder to lift, so storms require a larger buildup of energy before they can erupt. Once they do, that stored energy may feed taller convection columns, stronger winds, and more violent charge separation. NASA has also noted that Jupiter’s lightning likely forms in clouds containing an ammonia-water solution, adding another chemical twist absent from most terrestrial thunderstorms. That leaves Jupiter’s lightning as more than a planetary curiosity. It is becoming a diagnostic tool for understanding how giant planets work, and why atmospheres built from different gases can produce storms on scales Earth never approaches.
