The first 3D view of the buyer’s atmosphere

What happens under the clouds of gas giant Jupiter? Thanks to the data collected by the Juno probe, it was possible to create 3D images of the atmosphere that give clues to the invisible processes at work.

Juno has orbited Jupiter in 2016 and has orbited the planet 37 times so far. Thanks to its tools, it is able to examine what is happening under the cloud layer. The NASA He just reported publishing four scientific articles resulting from these observations and displaying the first 3D images of Jupiter’s atmosphere.

“Previously, Juno has surprised us by hinting that phenomena in Jupiter’s atmosphere were deeper than expected,” said Scott Bolton, a senior Juno researcher at the Southwest Research Institute in San Antonio and lead author of the published article. “Science” Deep swirls Jupiter. “We are now beginning to put all of these individual pieces together and get our first real understanding of how Jupiter’s beautiful and violent atmosphere works, in 3D.”

The new results show that hurricanes are hotter at the top, with lower atmospheric density, and cooler at the bottom, with higher intensity. Anticyclones, spinning in the opposite direction, are cooler at the top but warmer at the bottom. These storms are much higher than expected, with some extending 100 km below the cloud tops and others, including the Great Red Spot (a high pressure area), spanning at least 350 km. This surprising discovery shows that eddies cover regions outside of those where water condenses and clouds form and that lie below depth where sunlight heats the atmosphere.

The height and size of the Great Red Spot mean that the concentration of atmospheric mass within the storm could be detectable by instruments studying Jupiter’s gravitational field. Two missions from Juno over Jupiter’s most famous spot search for the storm’s gravitational signature and MWR (Microwave Radiometer) results on its depth. The conclusion published in another article written by “Science”:; The Great Red Spot is approximately 500 km deep below the cloud tops.

In addition to hurricanes and elevations, Jupiter is known for distinct belts and regions: clusters of white and red clouds that wrap around the planet. Strong east-west winds moving in opposite directions separate the bands. Juno had previously discovered that these winds, or jet streams, reached depths of about 3,200 kilometres. Researchers are still trying to solve the mystery of the formation of jet streams. Data collected by MWR Juno over several passes reveal possible evidence: atmospheric ammonia rises and falls in marked alignment with the observed jet streams.

“By tracking ammonia, we found circulation cells in the northern and southern hemispheres that are similar in nature to the ‘ferel cells’ that control much of our climate here on Earth,” said Keren Dorr, a graduate student at the Weizmann Institute. Science in Israel and lead author of an article by “Geophysical Research Letters”. “While Earth has one ferel cell per hemisphere, Jupiter has eight cells, each at least 30 times the size.” Each modifies the atmosphere’s composition locally, which may explain the colors of Jupiter’s bands.

Juno data also shows that belts and regions move about 65 kilometers under Jupiter’s water clouds. At shallower depths, Jupiter’s belts are much brighter in microwave light than neighboring regions. But at deeper levels, under water clouds, the opposite is true, revealing a resemblance to our oceans.

“We call this level the ‘jovicline’ in reference to the transition layer observed in Earth’s oceans, known as the thermocline (in which seawater changes abruptly from a relatively warm temperature to a relatively cold layer),” said Lee Fletcher, a university scientist. in the United Kingdom and lead author of the article in “Journal of Geophysical Research” Highlighting Juno’s microscopic observations of Jupiter’s belts and temperate regions.

Juno previously discovered polygonal arrangements of giant cyclonic storms at Jupiter’s poles: eight arranged in an octagon to the north and five arranged in a pentagon to the south. Now, five years later, scientists on the mission using observations from the Jovian Infrared Auroral Mapper (JIRAM) spacecraft have determined that these atmospheric phenomena are very flexible and stay in one place.

JIRAM data also indicates that these cyclones, like hurricanes on Earth, want to move toward the poles, but cyclones in the center of each pole are pushing them back. This report shows where hurricanes are located and the different numbers at each pole.