Juno results offer tantalizing hints of Jupiter’s secrets – Astronomy Magazine

Researchers also studied the planets immense magnetic field and found that close to the planet it was much stronger than expected, clocking in at 7.766 Gauss about ten times stronger than Earths. Their measurements also found lots of magnetic complexity near Jupiters outermost layers, which supports the hypothesis that the worlds magnetic field is being driven by the swirling liquid hydrogen layer beneath the clouds. A full mapping of the magnetic field awaits data from further Juno orbits.

Juno is giving us a view of the magnetic field close to Jupiter that weve never had before, said Jack Connerney, Junos deputy principal investigator. Already, we see that the magnetic field looks lumpy: It is stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen. Every flyby we execute gets us closer to determining where and how Jupiters dynamo works.

Understanding its magnetic field will add another piece to the puzzle of Jupiters interior. While planetary scientists assume it to be mostly hydrogen, the true composition, density and structure remain unknown. Scientists assume that the crushing pressures create a large layer of metallic hydrogen in the planets interior with a rocky core beneath, but definitive evidence is still lacking. Juno is also taking gravitational measurements as it orbits, which should give us more information about the interior as additional data becomes available.

In addition to looking below Jupiters clouds, the researchers wanted to see what happens above them, where charged particles from both the sun and within Jupiter interact with its magnetic field, creating huge auroras. Juno first encountered the shroud of particles last summer when it passed through the bow shock, a sort of shock wave created when Jupiters magnetic field shunts particles from the solar wind aside.The bow shock seems to have been moving outward as Juno passed through it, the researchers say.

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Juno results offer tantalizing hints of Jupiter's secrets - Astronomy Magazine