After NASA’s Juno probe in 2016 entered orbit around Jupiter, the spacecraft discovered giant cyclones arranged in geometric patterns around the world’s poles. At the north pole of the planet, there are eight vortices around a central vortex, and six at the south pole.
“We were surprised that Jupiter’s poles are not like other planets,” said study lead Cheng Cheng, a planetary scientist at the University of California, Berkeley, Space.com. “We had never seen anything before arranging these groups of cyclones in a regular pattern.”
related: Jupiter’s monster climbs on polar storms with this stunning NASA video
Each Gargyuan Temprest is 2,485 to 4,350 miles (4,000 to 7,000 kilometers) wide, and they circle their respective poles at a distance of 5,400 miles (8,700 km). These cyclones and these patterns have lasted for at least four years since Juno’s arrival on Jupiter.
It was a mystery to scientists how these groups remain stable. On Earth, cyclones drift polar, but spread over land and cold water, Lee said. In contrast, Jupiter has neither land nor ocean, raising the question of why cyclones did not just drift at the poles and merge. (For example, there is a cyclone on each pole of Saturn.)
“All previous theories predicted that the polar regions of giant planets should be dominated by large cyclones at their poles, such as what is being observed on Saturn, or remain chaotic,” said Lee, who is at Ann Arbor in Michigan. The university is taking a new position. . “What we see on Jupiter means that the previous theories are wrong, and we need something new.”
related: Solar system’s most powerful storm (photos)
To shed light on Jupiter’s cyclones, Xu and his colleagues developed computer models based on Juno’s disclosure of the size and speed of storms. They focused on which factors can keep these geometric patterns constant over time without merging.
Researchers found that the stability of these patterns depends partly on how low the cyclones reach Jupiter’s atmosphere, but mostly on the anticyclonic rings around each cyclone – that is, a ring of air moving in the opposite direction. Each cyclone is moving. Slight shielding from anticyclone rings occurred due to the merger of cyclones; Too much shielding can separate cyclones from one another.
There are many unresolved mysteries regarding these groups of cyclones. For example, it is unknown why Jupiter’s vortex occurs between too much and too little shielding at this happy middle. “Right now we have no idea what they need to do to sit in this sweet spot,” Lee said.
Scientists are now investigating how these cyclones may form in the first time. One possibility is that they formed near the poles where they are currently located. Secondly, “which we think is more likely, are they formed elsewhere and then gone to the pole,” Lee said.
Once researchers build computer models based on Juno’s data to see which of these formation scenarios is more likely, they can then begin to see how these cyclones find themselves in these stable patterns Let’s organize.
This may prove to be a more difficult question to answer, “because it involves detailed 3-D modeling of how these vortices are generated, and there are a lot of parameters about these vortices that we don’t know, such as That their vertical structure, ”Lee said. “But we can try different scenarios to see which vertical structures can generate the wind velocity profiles we’ve seen with these cyclones and move from there.”
The scientists detailed their findings online on 7 September in the journal Proceedings of the National Academy of Sciences.
Follow Charles Q. Choi on Twitter @cqchoi. Follow us on Twitter @Spacedotcom and Facebook.