Jupiter's magnetic field squished like a ball by solar winds
What's the story
A solar windstorm compressed Jupiter's magnetosphere like a "giant squash ball" back in 2017.
The revelation was made by scientists at the Keck Observatory in Hawaii, who noticed an unusual temperature spike in the gas giant's atmosphere.
The team from Reading University in England found unexpectedly high temperatures extending across half of Jupiter's circumference, reaching over 500 degree Celsius.
Temperature anomaly
How was the unusual temperature pattern detected?
Normally, Jupiter's intense polar auroras pump a lot of heat into its upper atmosphere at the poles. These auroras are much like Earth's, but more intense and energetic.
The researchers were taken aback by the unexpectedly high temperatures, which were much higher than the normal atmospheric background temperature of 350 degree Celsius.
They suggested this superheated region was likely "launched" toward the equator from the poles by a dense burst of solar wind.
Unprecedented discovery
Jupiter's response to solar wind recorded for 1st time
Lead author of the study, James O'Donoghue from the University of Reading, said they had never captured Jupiter's response to solar wind before.
He explained how it changed the planet's atmosphere in an unexpected way.
The compression of Jupiter's magnetosphere by solar wind seems to have intensified auroral heating at its poles, spilling hot gas generally confined to the poles, down toward the equator.
Frequency
Solar wind events occur 2 to 3 times monthly
O'Donoghue explained that the solar wind "squished Jupiter's magnetic shield like a giant squash ball," creating a super-hot region spanning half the planet.
Such solar wind events are believed to hit Jupiter two to three times per month.
This discovery challenges earlier assumptions that Jupiter's fast rotation would shield it from such effects, keeping auroral heating confined to the poles due to barriers created by strong winds.