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Abstract Interchange instability is known to drive fast radial transport of electrons and ions in Jupiter's inner and middle magnetosphere. In this study, we conduct a statistical survey to evaluate the properties of energetic particles and plasma waves during interchange events using Juno data from 2016 to 2023. We present representative examples of interchange events followed by a statistical analysis of the spatial distribution, duration and spatial extent. Our survey indicates that interchange instability is predominant atM‐shells from 6 to 26, peaking near 17 with an average duration of minutes and a correspondingM‐shell width of <∼0.05. During interchange events, the associated plasma waves, such as whistler‐mode, Z‐mode, and electron cyclotron harmonic waves exhibit a distinct preferential location. These findings provide valuable insights into particle transport and the source region of plasma waves in the Jovian magnetosphere, as well as in other magnetized planets within and beyond our solar system.
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This content will become publicly available on June 1, 2026
Determination of Jupiter’s primordial physical state
The formation and early evolution of Jupiter played a pivotal role in sculpting the large-scale architecture of the Solar System, intertwining the narrative of Jovian early years with the broader story of the Solar System's origins. The details and chronology of Jupiter's formation, however, remain elusive, primarily due to the inherent uncertainties of accretionary models, highlighting the need for independent constraints. Here we show that, by analysing the dynamics of Jupiter's satellites concurrently with its angular-momentum budget, we can infer Jupiter's radius and interior state at the time of the protosolar nebula's dissipation. In particular, our calculations reveal that Jupiter was 2 to 2.5 times as large as it is today, 3.8 Myr after the formation of the first solids in the Solar System. Our model further indicates that young Jupiter possessed a magnetic field of B♃† ≈ 21 mT (a factor of ~ 50 higher than its present-day value) and was accreting material through a circum-Jovian disk at a rate of M ̇ =1.2-2.4 M♃ Myr−1. Our findings are fully consistent with the core-accretion theory of giant-planet formation and provide an evolutionary snapshot that pins down properties of the Jovian system at the end of the protosolar nebula's lifetime.
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- Award ID(s):
- 2408867
- PAR ID:
- 10634578
- Publisher / Repository:
- Springer-Nature
- Date Published:
- Journal Name:
- Nature Astronomy
- Volume:
- 9
- Issue:
- 6
- ISSN:
- 2397-3366
- Page Range / eLocation ID:
- 835 to 844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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