Scientists report the results of the Juno mission
December 17, at a meeting of the American Geophysical Union in New Orleans, presented the results of studies of the Jupiter system, made by the spacecraft Juno (“Juno”). Scientists spoke about the study of the magnetic field of Jupiter and Ganymede, the dynamics of the planet’s atmosphere, and showed a picture of the thin dust ring surrounding the giant planet.
Jack Connerney of NASA’s Goddard Space Flight Center presented the most detailed map of Jupiter’s magnetic field to date. It is based on data collected over 32 complete orbits around the planet.
According to this map, the Big Blue Spot, a magnetic anomaly near Jupiter’s equator, has gradually evolved over Juno’s five-year orbit of the planet. The spot is drifting eastward at about 4 cm per second and should make a complete revolution relative to the surrounding layers of air in 350 years. Zonal winds (i.e. moving in the east-west and west-east directions) are tearing this slick apart. This fact means that zonal winds penetrate deep below the surface layer of the atmosphere.
The Great Red Spot, the famous anticyclone south of Jupiter’s equator, moves from east to west much faster. It makes a complete revolution in 4.5 years.
In addition, based on the map, scientists suggest that the magnetic field of Jupiter is responsible for a powerful dynamo effect in the metallic hydrogen, which is located in the interior of the planet under a layer of “helium rains”.
Juno mission science director Scott Bolton of the Southeastern Research Institute in San Antonio reported on data collected by the spacecraft’s magnetometer during a flyby near Ganymede on June 7, 2021. During its 34th orbit around Jupiter, Juno flew a distance of 1,038 km from the satellite’s surface. Its relative velocity during the flyby was 67,000 km/h.
Record of electric and magnetic fluctuations was made with the help of the device Waves. The attention of scientists attracted a noticeable jump in the frequency of oscillations, which indicates the hit of the spacecraft in a new region of Ganymede’s magnetosphere. Analysis of the data has not yet been completed, but scientists suggest that the jump is related to the movement of Juno from the shaded to the illuminated side of the satellite.
Bolton also presented an “audio recording,” for which the frequencies of the recorded oscillations were scaled and shifted into the sonic range.
Another presentation was given by Leah Siegelman, an oceanographer at the UCLA Institute of Oceanography. She noted that cyclones at Jupiter’s pole have similarities to ocean vortices on Earth, which she studied during her doctoral studies. The Jupiter pole model shows that structures in vortices on Jupiter arise spontaneously and persist throughout the observation period. This means that the basic geometric structure of the planet allows them to remain stable. And although Jupiter’s energy system is much larger than Earth’s, understanding the dynamics of Jupiter’s atmosphere can help us understand the physical mechanisms at work on our planet.
Finally, a team of scientists working with Juno presented an image of a light dust ring around Jupiter. It was taken with the spacecraft’s stellar sensor. The brightest of the thin bands in the photo are formed by two of Jupiter’s small moons, Metida and Adrastea. The “hand” of the constellation Perseus also appeared in the image.