Skip to main content

This is why the giant storms on Jupiter have existed for so long

NASA's Juno spacecraft, which entered a polar orbit around Jupiter in 2016, recorded gigantic storms on the gas planet. They occur in geometric patterns around the poles of the celestial body. How the giant hurricanes remain united in geometric patterns around the poles of Jupiter?

A storm in Jupiter. Cyclones on Jupiter.
How the storms actually came about is the subject of future studies.

Cyclones on Jupiter

After NASA's Juno probe entered into orbit around Jupiter in 2016, the probe discovered huge cyclones arranged in geometric patterns around the poles of Jupiter. 

At the north pole of the planet there are eight cyclones surrounding a central vortex, while at the south pole there are six. 
"We were surprised that the poles of Jupiter are not like the poles of other planets," told the leader of the study Cheng Li, a planetary researcher at the University of California, Berkeley. 
"We have never seen anything like these cyclone clusters, organized in regular patterns.
Spaceship Juno in November 2019 shows six cyclones, organized by hexagonal scheme at the south pole of Jupiter.
Spaceship Juno in November 2019 shows six cyclones, organized by hexagonal scheme at the south pole of Jupiter.

Each giant storm is between 2,485 and 4,350 miles wide (4,000 to 7,000 kilometers) and orbits around their poles at a distance of 8,700 km. These hurricanes and models have lasted at least four years since Juno's arrival at Jupiter.

It was a mystery to scientists how these clusters could remain stable

On Earth, cyclones drift, but they dissolve on earth and cold water, Li said. On the contrary, Jupiter has neither land nor oceans, which raises the question of why cyclones do not simply move to the poles and do not melt. (Saturn, for example, has only one cyclone at each of its poles).
"All previous theories predicted that the polar regions of giant planets should be dominated by large cyclones above their poles, like the one observed at Saturn, or remain chaotic," said Li, who is taking up a new position at the University of Michigan in Ann Arbor. 
"What we see in Jupiter means that previous theories are wrong and we need something new.

Shedding light on Jupiter's cyclones

Li and his colleagues developed computer models based on what Juno revealed about the size and speed of storms. They focused on what factors could keep these geometric models stable over time without merging.

The researchers found that the stability of these models depended partly on the depth at which cyclones descended into Jupiter's atmosphere, but mostly on the anticyclonic rings around each cyclone - a ring of wind that turns in the opposite direction to the direction in which each cyclone rotates. 

Too little shielding from the anticyclone rings caused the cyclones to melt; too much shielding could push the cyclones away.

There are many unsolved mysteries about these cyclone clusters. For example, it is not known why Jupiter's vortexes occupy this happy medium between too much and too little shielding. 
"At the moment we have no idea why they are in this sweet spot," said Li.
Scientists are now investigating how these vortexes could have formed in the first place. One possibility is that they formed near the poles where they are currently located. The other, "which we think is more likely, is that they formed elsewhere and then migrated to the poles," Li said.