Crazy mystery of Jupiter’s stunning color changes finally solved?

Images from a ground-based infrared telescope showing Jupiter in 5 micron wavelength radiation. One can see a marked change between May 2001 and December 2011 in the Northern Equatorial Belt (highlighted between dashed blue lines). Image Credit & Copyright: Arrate Antugnano/NASA/IRTF/NSFCam/SpeX

The researchers used data from NASA’s Juno mission to suggest that the change in Jupiter’s bands could be caused by torsional fluctuations in the planet’s magnetic field. These undulating motions may fill a gap in understanding between Jupiter’s surface phenomena and its deep inner phenomena, but further research is needed.

Scientists at the University of Leeds think they might be able to answer the long-standing mystery of Jupiter’s famous “bands”.

Images of the planet are characterized by colored bands, as well as the famous Great Red Spot, but these bands often move and change, which scientists have not yet been able to explain.

Now, with a new discovery made possible by NASA’s Juno mission providing incredible new information about Jupiter’s magnetic field, Dr. Kumiko Hori and Professor Chris Jones of the University School of Mathematics think they may have found the answer.

NASA’s Juno spacecraft is shown in orbit above Jupiter’s colorful clouds. Image Credit & Copyright: NASA/JPL-Caltech.

Professor Jones said: “If you look at Jupiter through a telescope, you will see bands that go around the equator along lines of latitude. There are dark and light belts, and if you look closely, you can see clouds rushing around with unusually strong east and west winds. Near the equator, the wind blows east, but if you change the latitude a bit, whether it’s north or south, it will go west. And then if you move a little further, it will go east again. This alternating pattern of easterly and westerly winds is very different from the weather on Earth.”

“The colors of the belts can change and sometimes the whole weather goes a little crazy, and it was a mystery why that happens.”
– Professor Chris Jones, University of Leeds School of Mathematics

“Every four or five years everything changes. The colors of the belts can change and sometimes you see global upheavals where the whole weather pattern goes a little crazy and it was a mystery why that was happening.”

Scientists already know that the change in Jupiter’s appearance is somehow related to infrared variations about 50 km below the gas giant’s surface, and a new study has shown that these variations, in turn, may be caused by waves created by the planet’s magnetic field deep inside. her bowels. .

Using data collected by NASA’s Juno mission to Jupiter, which has been orbiting the planet since 2016, their research team was able to track and calculate changes in its magnetic field.

Professor Jones added: “In the planetary magnetic field, you can get undulating motions called torsional vibrations. The most interesting thing is that when we calculated the periods of these torsional vibrations, they corresponded to the periods that you see in the infrared emission of Jupiter.”

The Juno spacecraft arrived at Jupiter in July 2016 after a nearly five-year journey from Cape Canaveral Air Force Base in Florida. Credit: NASA

Juno’s amazing longevity in Jupiter’s harsh radiation environment resulted in the probe staying in orbit much longer than originally planned. This led the Leeds researchers to obtain magnetic field data over a much longer period, which is much more useful for their work.

By observing the magnetic field for several years, they were able to trace its waves and fluctuations, and were even able to trace a special patch of the magnetic field on Jupiter called the Great Blue Spot. This slick has been moving east, but recent data shows that the movement is slowing, leading the Juno team to believe this is the start of a wobble, with the movement slowing down before turning around and moving west.

The work was led by Dr. Hori, who worked with Prof. Jones in Leeds before moving to a new position at Kobe University in Japan, along with Prof. Steve Tobias in Leeds, Prof. Lee Fletcher at the University of Leicester, and Dr. Arrate Antugnano at the Universidad del Pais Vasco in Spain .

They solved the long-standing riddle of Jupiter’s changing bands and bands, and filled in the missing link between two of Jupiter’s biggest fields of study – scientists interested in the planet’s weather and what’s happening on the surface, and those working in deep interior space.

“I hope our paper can also open a window to explore Jupiter’s hidden depths.”
– Dr. Kumiko Hori, Kobe University, Japan

Dr Hori said: “Uncertainties and questions remain, in particular how exactly the torsional vibrations cause the observed infrared variations, which likely reflect complex cloud/aerosol dynamics and responses. They need more research. However, I hope that our paper can also open a window to explore Jupiter’s hidden depths, just as seismology does for the Earth and helioseismology does for the Sun.”

For Professor Jones, the breakthrough was the culmination of a lifelong passion for Jupiter. He said: “I am incredibly pleased that NASA has finally been able to take a close look at Jupiter’s magnetic field. I’ve been studying Jupiter for an exceptionally long time, and I became interested in what’s under the surface of Jupiter when I was a kid – it’s been 60 years of progress.”

Reference: “Jupiter’s Cloud Level Variability Caused by Internal Torsional Oscillation” by Kumiko Hori, Chris A. Jones, Arrate Antugnano, Lee N. Fletcher, and Steven M. Tobias, May 18, 2023, Nature Astronomy.
DOI: 10.1038/s41550-023-01967-1