
During the general assembly of the European Geosciences Union General Assembly in Vienna, scientists of NASA’s Juno mission showed a 3D map that reproduces cyclones and anticyclones in the planet Jupiter’s polar regions. In particular, they created an animation of a flight over the North Pole. Using data collected by the Juno space probe they were also able to create the first detailed view of the dynamo that powers the planet’s magnetic field.
The Juno space probe’s Jovian InfraRed Auroral Mapper (JIRAM) instrument is the one that collected the data used to create these maps by capturing the light that emerges from the planet Jupiter’s depths. JIRAM probes Jupiter’s weather layer, which reaches the depth of about 3,000 kilometers (about 1,900 miles), but only for the first 50-70 kilometers (30-45 miles) under the clouds’ top.
These detections made it possible to gather the information needed for researchers to understand the forces at work. Jupiter’s North Pole is dominated by a central cyclone surrounded by eight circumpolar cyclones, which have diameters between 4,000 and 4,600 kilometers (between 2,500 and 2,900 miles). This is a unique situation, also because the various cyclones are very close and yet remain distinct so understanding the forces at work is essential to understand what’s happening in the polar regions.
Alberto Adriani of INAF in Rome, scientific director of the JIRAM instrument, explained that the Juno space probe, which entered the planet Jupiter’s orbit on July 4, 2016, allowed the collection of infrared images of Jupiter’s poles, areas that before scientists could only imagine. Now in its polar flybys Juno can gather information on weather patterns and cyclones with unprecedented resolution.
Concerning the research on the dynamo that powers the magnetic field of Jupiter, the Juno space probe also allowed to test models that were only theoretical. The belts of the planet’s atmosphere that we see rotating at different speeds extend up to a depth of about 3,000 kilometers (about 1,900 miles). Beyond it the hydrogen becomes so conductive that it’s dragged in an almost uniform rotation by the power of the Jovian magnetic field.
The information collected also allowed to map Jupiter’s magnetic field on its surface and below it, where the dynamo is thought to be originated. Jack Connerney of the Space Research Corporation in Annapolis explained that the observations show how that magnetic field is different from anything previously imagined. For researchers, Juno’s survey represents the beginning of a new era in the study of planetary dynamos.
NASA put online a video of the 3D animation. The areas shown in yellow are warmer (or deeper into Jupiter’s atmosphere) and the dark areas are colder (or higher). The highest temperature is 260 Kelvin (about -13° Celsius) and the lowest 190 Kelvin (about -83° Celsius).