Simulation of Io’s plumes and Jupiter’s plasma torus

Abstract

Io is a highly volcanic satellite of Jupiter. Its giant plumes rise hundreds of kilometers, creating large targets for incoming ions as Jupiter’s plasma torus overtakes Io in its orbit. Neutral material from Io’s sublimation atmosphere and volcanic plumes supplies the plasma torus, but the details of the interaction between neutral gas at Io and ions in the torus are not well understood. This paper suggests a process by which plume material is energized and ionized so as to supply the torus. We present three-dimensional direct simulation Monte Carlo simulations of giant plumes being bombarded by S+ and O+ ions which are moved based on precomputed electric and magnetic fields. The dependence of the plume/plasma interaction on the plume’s location on Io is investigated. The plume/plasma interaction is seen to be asymmetric even for a plume at the subplasma point because of the electric field that arises in an Io-fixed reference frame. Plasma is found to inflate and heat plume canopies and to give rise to a large, diffuse neutral cloud over the plume’s entire hemisphere. We also find that plasma can explain the thickness of red deposition rings observed on Io.

Morphology of the Io Plasma Torus From Juno Radio Occultations

“…Each of them is more or less regular and exhibits different magma, gas and dust supply. Third, the altitude, longitude and latitude of an ejection affect the interaction between the outgassing and the torus, determining if new material is ionized or if it fall back on Io's surface (McDoniel et al., 2019). As a last warning, the response of the IPT to plasma injection of different composition, temperature and density may be complex and it is still debated and under observation (Tsuchiya et al., 2018; Yoshikawa et al., 2017; Yoshioka et al., 2018).…”

In-situ detection of Europa’s water plumes is harder than previously thought

“…in Morabito et al (1979); Geissler and McMillan (2008)) and predicted by models (e.g. in Zhang et al (2003);McDoniel et al (2015McDoniel et al ( , 2019). The plumes on Enceladus do not exhibit the canopy shape observed at Io and predicted at Europa.…”

Variability of the Auroral Footprint of Io Detected by Juno‐JIRAM and Modeling of the Io Plasma Torus

“…Volcanic activity on Io may take different forms, like calderae, explosive and flow‐dominated eruptions and plumes (Davies, 2001; Lopes & Williams, 2015), and each of them can provide a different amount of gas and dust with different timings. Besides, the location of these events on Io's surface can affect the effective mass loading of the IPT (McDoniel et al., 2019). Furthermore, the new material from Io affects the properties of the atmosphere and ionosphere of the moon, which ultimately interacts with the IPT, affecting the effective mass loading of plasma, neutrals and dust into the Jovian magnetosphere (Delamere et al., 2004; Hikida et al., 2020; Koga et al., 2019; Yoneda et al., 2010, 2013).…”