# Presentation: 196174

## Field and Plasma Science with JIMO 

**Field and Plasma Science with JIMO**** **

**Krishan Khurana****1****, J. Hunter Waite****2****, William Kurth****3**** **
**1****SDT lead, Institute Geophys. Planet. Physics, UCLA,Kkhurana@igpp.ucla.edu**
**2****SDT co-lead, Dept. of ****Atmospheric, Oceanic, and Space Sciences****, Univ. of Michigan**
**3 ****Community lead, Department of Physics and Astronomy, University of Iowa**

## Contributors to this presentation

| SDT Members | Community members |
| --- | --- |
| Hunter Waite; Univ. Michigan | Barry Mauk;  APL Maryland |
| John Cooper; GSFC, Maryland | Chris Paranicas; APL Maryland |
| Jack Connerney; GSFC, Maryland | Bill Kurth; Univ. Iowa, Iowa. |
| Krishan Khurana; UCLA | Mike Combi; Univ. Michigan |
| Robert Johnson; Univ. Virginia | Jim Green; GSFC, Maryland  |
|  | Richard Thorne; UCLA |
|  | Mihaly Horanyi; Univ. Colorado, Boulder |
|  | Margaret Kivelson; UCLA |

## Introduction

**Field and plasma investigations straddle the realms of deep interiors, surfaces, atmospheres and exospheres of the icy satellites and Jupiter. **
**Magnetospheric and exospheric science**
**Field and plasma environments of the icy satellites**
**Plasma/dust/surface interactions**
**Satellite ionospheres and atmospheres**
**Studies of the Jovian magnetosphere**
**Geology and geophysics**
**Locating liquid water**
**Subsurface geology **
**Satellite interiors**

## Science Objectives

**Field and plasma environments of the icy satellites**
**Determine the effect of Jovian field, plasma and irradiation on the surfaces of the icy satellites.**
- Map the incident fluxes of energetic electrons, protons, and heavier ions (10 keV to tens of MeV energies) onto the moon surfaces for calculating irradiation effects versus depth including sputtering, implantation, and radiolysis.
- Characterize the changing field environment as the moons enter and emerge from the Jovian current sheet.
- Measure energetic neutral atom fluxes over time to understand the changing neutral and plasma toruses around the icy moons.
- Make active and passive measurements of the radio and plasma waves to determine local and distant electron densities.

## Science Objectives

**Plasma/dust/surface interactions**
**Characterize the irradiation induced Redox chemistry to understand if sufficient oxidants are subducted to the subsurface oceans to sustain biological activity.**
- Model the effect of incident fluxes of energetic electrons, protons, and heavier ions on moon surfaces.
**Characterize endogenic materials derived from the subsurface oceans and exogenic material derived from Jovian plasma.**
- Study recently picked-up thermal plasma populations (10 eV – 10 keV)
- Measure and model the ion cyclotron waves.
- Study composition of dust clouds in the vicinity of icy moons.
- Identify neutral components of the exospheres of the icy moons.
**Quantify Alfvenic interaction signature to improve estimates of the electromagnetic induction signature.**
- Measure the D.C. electric field directly and from phase space distributions of recently picked-up ions.
- Model vector field and plasma moments in the vicinity of the moon.

## Science Objectives ... continued

**Satellite ionospheres and atmospheres**
**Determine the structure and dynamics of the ionospheres and the neutral atmosphere associated with the moons’ exospheres to characterize the endogenic materials lofted from the surfaces.**
- Measure thermal population (10 eV – 10 KeV) in the ionospheres.
- Characterize sputtered material through techniques like neutral mass spectroscopy.
**Determine the source of Alfvenic conductivity in the vicinity of the icy moons.**
- Measure B field, electron and neutral densities in the ionospheres.
- Actively sound the ionosphere using low frequency plasma sounder.
**Determine the source(s) of polar aurorae on the icy satellites**
- Image the polar regions at all wavelengths.
- Measure plasma populations on the field lines threading the moons.

## Science Objectives ... continued

**Studies of the Jovian magnetosphere**
**Elucidate the role of solar wind electric field in causing convection in Jupiter’s magnetosphere. Investigate plasma and energy sources in the Jovian magnetosphere, upper atmosphere and the solar wind.**
- Study local time asymmetries in the magnetic field, electric currents, and thermal and energetic plasma populations in the inner and middle magnetosphere.
- Study Jovian aurorae at various wavelengths and relate to upstream solar wind conditions.
- Correlate dynamic spectral measurements of thermal and energetic particle populations at JIMO’s location to images of emissions from auroral surges at JIMO’s foot points in the upper atmosphere of Jupiter.
- Measure electron density in the magnetosphere from passive and active plasma sounding.
- Measure radio and plasma waves to determine the structure and dynamics of the magnetosphere and to understand the flow of mass and energy in the magnetosphere and the loss of particles to the atmosphere.
- Deconvolve ENA images of the magnetosphere to understand the sources and sinks of neutral and charged particles in Jupiter’s magnetosphere.

## Science Objectives ... continued

**Locating liquid water**
**Determine the existence, depth, and other characteristics of liquid oceans in the Galilean satellites.**
- Characterize  and model the electromagnetic induction response at multiple frequencies. Improve measurements by inferring local currents from plasma and plasma wave observations.
- Directly infer the ice/liquid water interface from the echoes of the low-frequency radar sounder (1 kHz – 40 MHz).

## Science Objectives ... continued

**Subsurface geology **
**Characterize the “dirtiness” of the ices of the satellites.**
- Measure the scattering properties and conductivity of ice near the surfaces of the Galilean satellites from the echoes of the low frequency radar sounder.

## Science Objectives ... continued

**Satellite interiors**
**Sound the deep interiors of the icy satellites to understand their origin and evolution.**
- Measure the internal dynamo generated magnetic fields in the icy satellites. Relate them to the known models of the interiors.
- Improve upon the in situ measurements of magnetic field by studying the loss cones of thermal and energetic ions.
- Measure the electromagnetic induction signal at several frequencies to probe through the oceans to understand the deep interiors of the icy satellites.

## The end