<table><caption>**Table 3** (Continued)</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>GE.2f. Map non-water-ice materials (including organics and products of radiolysis and ion bombardment, e.g. H<sub>2</sub>O<sub>2</sub>, O<sub>3</sub>, H<sub>2</sub>CO, H<sub>2</sub>CO<sub>3</sub>) and their association with known geologic features over the wavelength range of 100 nm to 200 nm with spectral resolution better than or equal to 2 nm. Requires at least 50% coverage with spatial resolution ≤3 km/px.</td><td>UVS</td></tr><tr><td></td><td></td><td>GE.2g. Map non-water-ice materials (including potential organics and products of radiolysis and ion bombardment, e.g. H<sub>2</sub>O<sub>2</sub>, O<sub>3</sub>, H<sub>2</sub>CO, H<sub>2</sub>CO<sub>3</sub>) and their association with known geologic features over the wavelength range of 400-nm to greater than or equal to 5.0 microns with spectral resolution better than or equal to 5 nm from 400 nm to 2.0 microns; better than or equal to 10 nm from 2.0 to greater than or equal to 5.0 microns. Requires at least 50% coverage with spatial resolution between 2 and 3 km/px. Determine the origin and evolution of non-water-ice materials by making measurements in the wavelength range from 0.4 to at least 5.0-microns with a spectral resolution better than or equal to 10 nm and a spatial resolution better than or equal to 125 m/px of representative features. Co-register with higher-resolution monochromatic images at better than or equal to 100 m/px (see GE.2a).</td><td>MAJIS</td></tr><tr><td rowspan="3">GE.3</td><td rowspan="3">Investigate surface composition and structure on open vs. closed field line regions.</td><td>GE.3a. Map several known or expected tracer species of weathering effects induced by the magnetosphere (e.g., H<sub>2</sub>O, CO<sub>2</sub>, NH<sub>3</sub>, O<sub>3</sub>, H<sub>2</sub>O<sub>2</sub>, H<sub>2</sub>SO<sub>4</sub> hydrate, etc.) over the wavelength range of 100 to 200 nm with spectral resolution ≤ 5 nm. Requires at least 50% coverage with spatial resolution ≤ 3 km/px.</td><td>UVS</td></tr><tr><td>GE.3b. Map several known or expected tracer species of weathering effects induced by the magnetosphere (e.g., H<sub>2</sub>O, CO<sub>2</sub>, NH<sub>3</sub>, O<sub>3</sub>, H<sub>2</sub>O<sub>2</sub>, H<sub>2</sub>SO<sub>4</sub> hydrate, etc.) over the wavelength range of 1.0 to 2.0 µm with a spectral resolution better than or equal to 5 nm and 2.0 to at least 5 µm with a spectral resolution less than or equal to 10 nm. Requires at least 50% coverage with spatial resolution between 2 and 3 km/px. Map the distribution of the state of water ice (crystalline vs. amorphous) as a function of the latitude, in the spectral range from 1.0- to 4.0-µm with spectral resolution less than or equal to 10 nm. Map targeted features to assess local conditions (albedo) in the 0.4- to 1.0-µm range. Requires at least 50% coverage with spatial resolution between 2 and 3 km/px.</td><td>MAJIS</td></tr><tr><td>GE.3c. Measure three-axis magnetic field components at 32 to 128 Hz and with a resolution of 0.1 nT at different orbital phases and distances less than 0.5 moon radii.</td><td>JMAG</td></tr></tbody></table>
<table><caption>**Table 3 (Continued)**</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>GE.3d. Global monochromatic imaging at 400 m/px with selected features mapped in 4 colors (e.g. 0.4-µm, 0.5-µm, 0.7-µm, 0.9-µm) at 100 m/px. Targeted imaging at a resolution of better than 30 m/px over regions of interest.</td><td>JANUS</td></tr><tr><td></td><td></td><td>GE.3e. Identify open and closed field lines with an latitudinal accuracy of ≤1° in Ganymede circular orbit by measuring electrons in opposing directions with a time resolution of ≤20 s. Measure neutral exospheric composition with sufficient sensitivity and to sufficient mass resolution to identify major volatile species with mixing ratios better than 1%. Determine the particle precipitation zones by measuring (in-situ) the precipitating electrons and ions (major magnetospheric species) in the 10's eV to MeV energy range, and by imaging the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°.</td><td>PEP</td></tr><tr><td></td><td></td><td>GE.3f. Measure electron and ion density (10<sup>-4</sup>-10<sup>5</sup>/cm<sup>3</sup>) and electron temperature (0 to 100 eV), as well as constrain ion temperature (0 to 20 eV) on open versus closed field lines. Determine charge level on dust population by measuring the electron and ion densities (10<sup>-4</sup>-10<sup>5</sup>/cm<sup>3</sup>), and the spacecraft potential at +/-100 V at 1 V accuracy. Measure the DC electric field vector (DC-1 kHz) to monitor electrostatic acceleration structures and Alfvén waves that accelerate charged particles toward surface.</td><td>RPWI</td></tr><tr><td rowspan="4">GE.4</td><td rowspan="4">Determine volatile content to constrain satellite origin and evolution.</td><td>GE.4a. Measure the stable isotopes of C, H, O, and N in the major volatiles (e.g. H<sub>2</sub>O, CH<sub>4</sub>, NH<sub>3</sub>, CO, CO<sub>2</sub>, SO<sub>2</sub>), and measure the noble gases Ar, Kr, and Xe, with mass resolution better than 500. Characterise the composition of sputtered desorbed volatiles over a mass range better than 300 Daltons with mass resolution better than 500.</td><td>PEP</td></tr><tr><td>GE.4b. and the 17O/16O and 18O/16O ratio in water ice from limb observations of water rotational transitions in the 600 GHz band. Identify globally distributed bulk material composition from polarized continuum observations of the surface in the 600 GHz band under different off-nadir angles.</td><td>SWI</td></tr><tr><td>GE.4c. Identify and map non-water-ice materials over a wide range of spatial scales (from 5 km/px to 1 km/px or better), in the overall spectral range 0.1-0.2 micron and with a spectral resolution better than or equal to 2 nm, suitable to discriminate various volatiles known or expected to exist on the surface. Requires at least 50% coverage with spatial resolution ≤ 3 km/px.</td><td>UVS</td></tr><tr><td></td><td></td><td></td><td></td></tr></tbody></table>
<table><caption>**Table 3** (Continued)</caption><thead><tr><td>Objectives</td><td>Investigations</td><td>Measurement Requirements</td><td>Instruments</td></tr></thead><tbody><tr><td></td><td></td><td>GE.4d. Identify and map non-water-ice materials over a wide range of spatial scales (from 5 km/px to 1 km/px or better), in the overall spectral range 0.4 to greater than or equal to 5 µm and with a spectral resolution better than or equal to 5 nm from 0.4 to 2.0 µm and better than or equal to 10 nm from 2.0 to greater than or equal to 5 µm, suitable to discriminate various volatiles known or expected to exist on the surface. Requires at least 50% coverage with spatial resolution between 2 and 3 km/px. Identify globally distributed bulk material composition in the spectral range from 1.0 to at least 5.0 µm with a spectral resolution better than or equal to 10 nm and over a wide range of spatial scales (from 10 km/px to 100 m/px or better).</td><td>MAJIS</td></tr></tbody></table>

<table><caption>**Table 4** Europa</caption><thead><tr><td>Science Objectives</td><td>Science Investigations</td><td>Measurement Requirements</td><td>Instruments</td></tr></thead><tbody><tr><td rowspan="4">EA. Determine the composition of the non-ice material, especially as related to habitability</td><td rowspan="4">EA.1 Characterise surface organic and inorganic chemistry, including abundances and distributions of materials, with emphasis on essential elements for habitability and potential biosignatures.</td><td>EA.1a. Measure surface reflectance of large areas across the dayside, at a spatial resolution between 2.5 and 10 km/px, through a spectral range from 0.4 to 2.0 µm with a spectral resolution of better than or equal to 5 nm, and from 2.0 µm to at least 5 µm with a spectral resolution better than or equal to 10 nm. Targeted characterization of selected sites of very high interest should be at a spatial resolution of better than or equal to 100 m-1 km/px.</td><td>MAJIS</td></tr><tr><td>EA.1b. Measure surface reflectance of large areas across the dayside, at a spatial resolution <50 km/px, through a spectral range of at least 110 to 200 nm with ≤ 3-nm spectral resolution. Targeted characterization of selected sites of very high interest should be at a spatial resolution of better than or equal to ~1 km/px.</td><td>UVS</td></tr><tr><td>EA.1c. Characterise the composition of sputtered surface products over a mass range better than 300 Daltons, mass resolution better than 500. Image the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°.</td><td>PEP</td></tr><tr><td>EA.1d. Correlate surface composition and physical characteristics (e.g., grain size) with geologic features through 3-color mapping at resolution of better than 2 km/px over the dayside, including selected sites of very high interest at spatial resolutions better than 0.5 km/px.</td><td>JANUS</td></tr></tbody></table>
<table><caption>**Table 4 (Continued)**</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td rowspan="7">EA.2 Relate material composition and distribution to geological features and geological processes, especially material exchange with the interior.</td><td>EA.2a. Measure surface reflectance of large areas across the dayside, at a spatial resolution between 2.5 and 10 km/px, through a spectral range from 0.4 to 2.0 µm with a spectral resolution of better than or equal to 5 nm, and from 2.0 µm to at least 5 µm with a spectral resolution better than or equal to 10 nm. Targeted characterization of selected sites of very high interest should be at a spatial resolution of better than or equal to ~100 m-1 km/px.</td><td>MAJIS</td></tr><tr><td>EA.2b. Measure surface reflectance of large areas across the dayside, at a spatial resolution &lt;50 km/px, through a spectral range of at least 110 to 200 nm with ≤ 3-nm spectral resolution. Targeted characterization of selected sites of very high interest should be at a spatial resolution of better than or equal to ~1 km/px.</td><td>UVS</td></tr><tr><td>EA.2c. Characterize subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth) by means of subsurface profiles of selected sites of at least 30-km in length.</td><td>RIME</td></tr><tr><td>EA.2d. Determine the distributions and morphologies of surface landforms at regional and local scales, through monochromatic imaging with resolution better than or equal to 0.5 km/px. Constrain regional and global stratigraphic relationships by determining surface color characteristics at better than 2 km/px scale in at least 3 colors with near-uniform lighting conditions and solar phase angles less than or equal to 45 degrees, over large areas across the dayside. Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50 meter vertical resolution over regions of high interest, and along subsurface profiles for generation of DTM for RIME data interpretation.</td><td>JANUS</td></tr><tr><td>EA.2e. In regions co-located with subsurface profiles: Acquire precise topography with a vertical resolution of 1 m along-track at 100-meter (goal: a few tens of meters) horizontal resolution. Determine surface roughness on the scale of 80 to 40 m or better during flybys from the laser return pulse.</td><td>GALA</td></tr><tr><td>EA.2f. Perform radiometric-polarized measurements in the 600 GHz band and under different off-nadir angles to constrain the thermophysical properties of the ice, regolith and ice-regolith mixtures down to a depth of a few cm.</td><td>SWI</td></tr><tr><td>EA.2g. Measure the volatile content of potential outgassing sources from the shallow subsurface or deeper interior and relate them to the origin and evolution of the satellite, over a mass range better than 300 Daltons, mass resolution better than 500.</td><td>PEP</td></tr></tbody></table>
<table><caption>**Table 4** (Continued)</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td>EA.3 Characterization of the backscattered and sputtered material from the surface</td><td>EA.3a. Measure the stable isotopes of C, H, O, and N in the major volatiles (e.g. H<sub>2</sub>O, CH<sub>4</sub>, NH<sub>3</sub>, CO, CO<sub>2</sub>, SO<sub>2</sub>), measure the noble gases Ar, Kr, and Xe, with mass resolution better than 500, and characterise the composition of sputtered desorbed volatiles over a mass range better than 300 Daltons and mass resolution better than 500. Determine the particle precipitation by measuring (in-situ) electrons and ions (major magnetospheric species) in the 10's eV to MeV energy range. Image the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°.<br>EA.3b. Determine the plasma waves and cold plasma characteristics with good time resolution (&lt;10 s). Determine mass and size distribution of dust for sizes &gt;1 µm. Measure electron and ion density (10<sup>-4</sup>-10<sup>5</sup>/cm<sup>3</sup>) and electron temperature (0.01-100 eV), as well as the ion ram speed (&lt;200-km/s). Constrain ion temperature (&lt;20 eV). Determine the presence of suprathermal electrons and plasma inhomogenities (dn/n, 0-10 kHz). Determine energy transport by Alfvén- and plasma waves between populations, by measuring the electric (DC-45 MHz) and magnetic field (0.1 Hz-20 kHz) vectors.<br>EA.3c. Measure three-axis magnetic field components at 32 to 128 Hz and with a resolution of 0.1 nT to observe ion cyclotron waves; relate these waves to neutral ionization and plasma pickup in order to constrain sputtering rates.<br>EA.3d. Measure ionospheric electron density profiles for different locations and infer correlations with solar zenith angle, magnetospheric location and surface characteristics.<br>EA.3e. Measure surface reflectance of large areas across the dayside of Europa, at a spatial resolution &lt;50 km/px, through a spectral range of at least 110 to 200 nm, with ≤ 3 nm spectral resolution, along with targeted characterization of selected sites of very high interest at a spatial resolution of better than or equal to ~1 km/px.<br>EA.3f. Determine the distributions and morphologies of surface landforms at regional and local scales, through monochromatic imaging with resolution better than or equal to 0.5 km/px. Constrain regional and global stratigraphic relationships by determining surface color characteristics at better than 2 km/px scale in at least 3 colors with near-uniform lighting conditions and solar phase angles less than or equal to 45 degrees, over large areas across the dayside. Determine surface color characteristics at ~500 m/px scale in at least 3 colors.</td><td>PEP<br>RPWI<br>JMAG<br>3GM<br>UVS<br>JANUS</td></tr></tbody></table>
<table><caption>**Table 4** (Continued)</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>EA.3g. Measure surface reflectance of large areas across the dayside, at a spatial resolution between 2.5 and 10 km/px, from 0.4 to 2.0 µm with a spectral resolution of better than or equal to 5 nm, and from 2.0 µm to greater than or equal to 5 µm with a spectral resolution better than or equal to 10 nm, along with targeted characterization of selected sites of very high interest at a spatial resolution of better than or equal to ~1 km/px.</td><td>MAJIS</td></tr><tr><td rowspan="3">EB. Look for liquid water under the most active sites</td><td>EB.1. Surface and Subsurface exploration of the icy crust below young and resurfaced areas to look for water reservoirs</td><td>EB.1a. Identify and locally characterise subsurface thermal or compositional horizons and structures related to the current or recent presence of water or brine, by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth).<br>EB.1b. In regions co-located with subsurface profiles: Acquire precise topography with a vertical resolution of 1 m along-track at 100-meter (goal: a few tens of meters) horizontal resolution.<br>EB.1c. Determine the distributions and morphologies of surface landforms at regional and local scales, through monochromatic imaging with resolution better than or equal to 0.5 km/px. In regions co-located with subsurface profiles: Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50-meter vertical resolution.</td><td>RIME<br>GALA<br>JANUS</td></tr><tr><td>EB.2. Determine minimal thickness of the icy crust on most active regions</td><td>EB.2a. Identify and locally characterise subsurface thermal or compositional horizons and structures related to the current or recent presence of water or brine, by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth).<br>EB.2b. In regions co-located with subsurface profiles: 1) Acquire precise topography with a vertical resolution of 1 m along-track at 100-meter (goal: a few tens of meters) horizontal resolution.<br>EB.2c. In regions co-located with subsurface profiles: Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50-meter vertical resolution.</td><td>RIME<br>GALA<br>JANUS</td></tr><tr><td>EB.3. Search for possible active regions on the surface of Europa (plumes etc.)</td><td>EB.3a. Identify and locally characterise subsurface thermal or compositional horizons and structures related to the current or recent presence of water or brine, by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth).</td><td>RIME</td></tr></tbody></table>
<table><caption>**Table 4** (Continued)</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>EB.3b. Characterise the detailed three-dimensional surface morphology of targeted features at a few 10s of meters horizontal scale and 1 meter vertical accuracy across the target, co-located with subsurface profiles.</td><td>GALA</td></tr><tr><td></td><td></td><td>EB.3c. Determine surface color characteristics at ~500 m/px scale in at least 3 colors, colocated with subsurface profiles. Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50 meter vertical resolution over regions of high interest.</td><td>JANUS</td></tr><tr><td></td><td></td><td>EB.3d. Determine the distribution function of electrons and ions with sufficient angular and energy coverage to derive plasma density and velocity. Measure ion composition with first-order mass resolution. Measure the volatile content of potential outgassing sources from the shallow subsurface or deeper interior and relate them to the origin and evolution of the satellite, over a mass range better than 300 Daltons, mass resolution better than 500.</td><td>PEP</td></tr><tr><td></td><td></td><td>EB.3e. Measure three-axis magnetic field components at 32 to 128 Hz and with a resolution of 0.1 nT to observe ion cyclotron waves; relate these waves to neutral ionization and plasma pickup in order to detect and constrain neutral sources.</td><td>JMAG</td></tr><tr><td></td><td></td><td>EB.3f. Determine plasma wave, electrodynamics and cold plasma characteristics with good time resolution (&lt; 10 s). This requires the full range of measurements of electric field vectors (DC-45 MHz), magnetic field vectors (0.1-20 kHz), density perturbations (δn/n, DC-10 kHz), electron and ion densities (10<sup>-4</sup>-10<sup>5</sup>/cm<sup>3</sup>), electron temperature (0.01-100 eV), ion drift speed (&lt;200 km/s), spacecraft potential (+/-100 V), and the mass and size distribution of dust for dust &gt;1 µm. The DC electric field measurements need an accuracy better than 1 mV/m.</td><td>RPWI</td></tr><tr><td></td><td></td><td>EB.3g. Search for high gradients in the water exosphere near the surface by measuring the rotational ground state of water vapour at 557 GHz</td><td>SWI</td></tr><tr><td>EC. Study the EC.1 active processes</td><td>Study the interaction between the local environment and (a) the Europa torus, (b) the effects of radiation on surface chemistry, and (c) sputtering processes</td><td>EC.1a. (a) Determine the global, relative variability and distribution of Europa neutral torus (and possible plasma component) through remote ENA imaging in the 10's eV - 100 keV range (first order mass resolution) with ≤7° angular resolution on 10 h time scales. Determine the local pitch-angle distributions of ions in the 10-100's keV range of major magnetospheric ion species. Measure plasma electron densities. (b)-(c) Determine the particle precipitation by measuring (in-situ) the electrons and ions (major magnetospheric species) in the 10's eV to MeV energy range, and by imaging the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°.</td><td>PEP</td></tr></tbody></table>
<table><caption>**Table 4** (Continued)</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>EC.1b. Measure three-axis magnetic field components at 32 Hz and obtain 180 degrees plasma pitch angle coverage with time resolution of seconds to determine temporal and spatial changes of field-aligned vs. trapped particle distributions.</td><td>JMAG</td></tr><tr><td></td><td></td><td>EC.1c. Determine plasma wave, electrodynamics and cold plasma characteristics with good time resolution (&lt; 10 s). This requires the full range of measurements of electric field vectors (DC-45 MHz), magnetic field vectors (0.1-20 kHz), density perturbations (δn/n, DC-10 kHz), electron and ion densities (10<sup>-4</sup>-10<sup>5</sup> /cm<sup>3</sup>), electron temperature (0.01-100 eV), ion drift speed (&lt;200 km/s), spacecraft potential (+/−100 V), and the mass and size distribution of dust for dust &gt; 1 µm. The DC electric field measurements need an accuracy of 1 mV/m.</td><td>RPWI</td></tr><tr><td></td><td></td><td>EC.1d. Determine surface color characteristics at ~500 m/px scale in at least 3 colors. Global view by imaging of the sodium exosphere with a spatial resolution of better than 20 km/px</td><td>JANUS</td></tr><tr><td>EC.2</td><td>Observe the limb for activity</td><td>EC.2a. Perform stellar occultations and measure atmospheric emissions plus surface reflectance at better than or equal to 1 km/px spatial resolution in the wavelength range of 100 to 200 nm with &lt; 2 nm spectral resolution. Obtain limb views for stellar occultations, including bulk photometric light curves for plume searches, and obtain surface profiles with less than or equal to 25-km spacing. Perform scans perpendicular to the limb from ~5 km above the surface to the surface of the satellite in the wavelength range of 100 nm to 200 nm (spectral resolution of 2 nm) to measure or search for emission from O (135.6 nm) and other species in the atmosphere.</td><td>UVS</td></tr><tr><td></td><td></td><td>EC.2b. Perform scans perpendicular to the limb from ~5 km above the surface to the surface of the satellite in the wavelength range of 0.4 micron to greater than 5.0 microns (spectral resolution better than or equal to 5 nm below 2.0 microns and better than or equal to 10 nm from 2.0 to at least 5.0 microns) to measure or search for emission from O<sub>2</sub> (1.27 microns), H<sub>2</sub>O, CO<sub>2</sub> (4.26 microns) and other species in the atmosphere.</td><td>MAJIS</td></tr><tr><td></td><td></td><td>EC.2c. Determine the distribution of water vapour from water line observations in the 600 GHz band.</td><td>SWI</td></tr></tbody></table>
<table><caption>**Table 4 (Continued)**</caption><thead><tr><th>Science Objectives</th><th>Science Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td rowspan="3">EC.3</td><td rowspan="3">Look for surface changes w.r.t. Galileo observations</td><td>EC.3a. Detailed morphological characterization of targeted features at better than or equal to 50 m/px spatial scale, and solar incidence angles between 30° and 70°, ideally with stereo. Co-located with imaging at approximately 10 times wider swath and not worse than 10 times coarser resolution. Correlate surface composition and physical characteristics (e.g., grain size) with geologic features through 3-color mapping at resolution of better than 2 km/px over the dayside of Europa, including selected sites of very high interest at spatial resolutions better than 0.5 km/px.</td><td>JANUS</td></tr><tr><td>EC.3b. Measure surface reflectance of large areas across the dayside of Europa, at a spatial resolution &lt;50 km/px, in the UV</td><td>UVS</td></tr><tr><td>EC.3c. Measure surface reflectance of large areas across the dayside of Europa, at a spatial resolution between 2.5 and 10 km/px, from the Vis to the IR.</td><td>MAJIS</td></tr></tbody></table>

<table><caption>**Table 5 Callisto**</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td rowspan="3">CA.</td><td rowspan="3">Characterise the outer shells, including the ocean.</td><td>CA.1a. Measure subsurface dielectric properties and estimate density of buried scatterers in targeted regions by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth).</td><td>RIME</td></tr><tr><td>CA.1b. In regions co-located with subsurface profiles: Acquire precise topography at 1 meter vertical resolution along-track at 100-meter (goal: a few tens of meters) horizontal resolution.</td><td>GALA</td></tr><tr><td>CA.1c. Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50 meter vertical resolution over regions of high interest and along subsurface profiles for generation of DTM for RIME data interpretation.</td><td>JANUS</td></tr><tr><td rowspan="2">CA.2</td><td rowspan="2">Characterise the space plasma environment to determine the magnetic induction response from Callisto's ocean.</td><td>CA.2a. Measure three-axis magnetic field components at 32 to 128 Hz with a resolution of 0.1 nT across multiple flybys at different orbital phases to determine the induction response at multiple frequencies (related to satellite orbital and Jupiter rotation time scales).</td><td>JMAG</td></tr><tr><td>CA.2b. Determine the distribution functions for electrons and ions (first order mass resolution) with an angular and energy coverage sufficient to determine the cold plasma density and velocity to constrain contributions from currents not related to the surface and ocean.</td><td>PEP</td></tr></tbody></table>
<table><caption>**Table 5** (Continued)</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>CA.2c. Measure electric field vectors from DC to 1.6 MHz better than &lt;1 mV/m accuracy. Measure the vector magnetic field variations at 0.1 Hz-20 kHz. Together with electron and ion density (10<sup>-4</sup> to 10<sup>5</sup>/cm<sup>3</sup>) measurements with better than 20% accuracy, determine conductivity and electrical currents. Measure electron temperature (0.01-100 eV) and the ion drift speed (&lt;200 km/s).</td><td>RPWI</td></tr><tr><td>CB.<br>Determine<br>the<br>composition<br>of the non-ice<br>material</td><td>CB.1<br>Characterise<br>surface organic<br>and inorganic<br>chemistry,<br>including<br>abundances and<br>distributions of<br>materials and<br>volatile<br>outgassing.</td><td>CB.1a. Identify and map non-water-ice materials (including organic compounds and radiolytic materials) over a wide range of spatial scales (from 5 km/px to 100 m/px or better), with a spectral resolution (better than or equal to 5 nm from 0.4 to 2.0 µm and better than or equal to 10 nm from 2.0 to greater than or equal to 5 µm) suitable to discriminate various compounds known or expected to exist on the surface. Determine bulk material composition, grain size, porosity, crystallinity, and physical state of water ice in the spectral range from 1 to 4 microns with a spectral resolution better than or equal to 10 nm over a wide range of spatial scales (from 10 km/px to 100 m/px or better) and illumination conditions. Determine the composition, distribution and physical characteristics (grain-size, physical state) of volatile materials on the surface. Determine the origin and geologic evolution of non-water-ice materials, including the role of geologic processes by making observations in the wavelength range from 0.4 to at least 5 µm with a spectral resolution better than or equal to 10 nm and spatial resolution better than or equal to 1 km/px of representative features. Observations need to be co-registered with higher-resolution panchromatic images.<br>CB.1b. Acquire two-dimensional spectral-spatial images in the range 100 to 200 nm with a spectral resolution better than or equal to 2 nm and a spatial resolution from 5 km/px to 1 km/px or better. Determine the composition, distribution and physical characteristics (grain-size, physical state) of volatile materials on the surface, including measurements in the wavelength range of 100- to 200 nm at 2 nm spectral resolution to identify O<sub>3</sub>, H<sub>2</sub>O<sub>2</sub> and other species.<br>CB.1c. Measure the volatile content (i.e. water, carbon PEP dioxide, methane, ammonia, and noble gases) of potential outgassing sources from the near subsurface or deeper interior over a mass range better than 300 Daltons with a mass resolution better than 500. Characterise the composition of sputtered surface products over a mass range better than 300 Daltons, mass resolution better than 500. Image the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution &le;100% and angular resolution &le;7°.</td><td>MAJIS<br>UVS</td></tr></tbody></table>
<table><caption>**Table 5 (Continued)**</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>CB.1d. Image at medium-resolution (~100's m/px) to characterize large parts of the surface in four spectral band passes (e.g. 0.4, 0.67, 0.76, 1.0 µm) in the wavelength range of 350 nm to 1.0 µm including multiphase coverage for measurements of surface physical properties. Acquire high-resolution (better than 50 m/px) imaging of selected targets. Requires repeat pass coverage of areas of interest to assess temporal variations. Determine the origin and geologic evolution of non-water-ice materials, including the role of geologic processes by making high-resolution panchromatic images (&lt;1 km/pxl) of representative features.</td><td>JANUS</td></tr><tr><td></td><td></td><td>CB.1e. Identify globally distributed bulk material composition from polarized continuum observations of the surface in the 600 GHz band under different off-nadir angles.</td><td>SWI</td></tr><tr><td></td><td></td><td>CB.1f. Characterize the ionized part of the volatile outgassing by measuring the electron and ion densities (10<sup>-4</sup>–10<sup>5</sup>/cm<sup>3</sup>) and ion drift speed (&lt;200 km/s) close to Callisto with good time resolution (&lt; 10 s). This requires also measurements of electric field vectors (DC–45 MHz), magnetic field vectors (0.1–20 kHz), density perturbations (δn/n, DC–10 kHz), electron temperature (0.01–100 eV), spacecraft potential (+/–100 V), and the mass and size distribution of dust for dust &gt; 1 µm. The DC electric field measurements need an accuracy better than 1 mV/m.</td><td>RPWI</td></tr><tr><td>CB.2</td><td>Relate material composition and distribution to geological and magnetospheric processes.</td><td>CB.2a. Map large parts of the surface at medium resolution (~100's m/px) in four spectral band passes (e.g. 0.4 µm, 0.67 µm, 0.76 µm, 1.0 µm) in the wavelength range of 350 nm to 1.0 µm.</td><td>JANUS</td></tr><tr><td></td><td></td><td>CB.2b. Identify surface modifications due to external plasma and particle interactions by measuring (in-situ) the precipitating electrons and ions (major magnetospheric species) in the 10's eV to MeV energy range, and by imaging the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°. Determine the variable Jovian magnetospheric environment local to Ganymede by imaging ENAs in the 10–100's keV range produced with an angular resolution ≤10° (first order mass resolution) with a time resolution of 1 h. Measure neutral exospheric composition with sufficient sensitivity and to sufficient mass resolution to identify major volatile species with mixing ratios better than 1%. Requires open source positive ion spectrum to characterize the composition of ionospheric plasma, open source neutral spectrum for density profiles of sputtered species, and closed source neutral spectrum.</td><td>PEP</td></tr></tbody></table>
<table><caption>**Table 5 (Continued)**</caption><thead><tr><td>Objectives</td><td>Investigations</td><td>Measurement Requirements</td><td>Instruments</td></tr></thead><tbody><tr><td></td><td></td><td>CB.2c. Measure the surface reflectance in the wavelength range from 0.4 to at least 5 µm to identify surface composition and relate it to geologic units and weathering processes. Identify and map the distribution of products of radiolysis and ion bombardment (e.g. H<sub>2</sub>O<sub>2</sub>, O<sub>3</sub>, H<sub>2</sub>CO, H<sub>2</sub>CO<sub>3</sub>) over the wavelength range from 1.0 to 2.0 µm at better than or equal to 5 nm spectral resolution and from 2.0 to greater than or equal to 5 µm at better than or equal to 10 nm spectral resolution.</td><td>MAJIS</td></tr><tr><td></td><td></td><td>CB.2d. Measure the surface reflectance in the wavelength range from 0.1 to 0.2 µm to identify surface composition and relate it to geologic units and weathering processes. Identify and map the distribution of products of radiolysis and ion bombardment (e.g. H<sub>2</sub>O<sub>2</sub>, O<sub>3</sub>, H<sub>2</sub>CO, H<sub>2</sub>CO<sub>3</sub>) over the wavelength range of 100 to 200 nm with spectral resolution better than or equal to 2 nm.</td><td>UVS</td></tr><tr><td></td><td></td><td>CB.2e. Perform radiometric-polarized measurements in the 600 GHz band and under different off-nadir angles to constrain the thermophysical properties of the ice, regolith and ice-regolith mixtures down to a depth of a few cm.</td><td>SWI</td></tr><tr><td></td><td></td><td>CB.2f. Detect dust and determine its mass and size distribution with electric field (DC to 45 MHz). Determine charge level on dust population by measuring the electron and ion densities (10<sup>-4</sup>–10<sup>5</sup>/cm<sup>3</sup>), and the spacecraft potential at +/-100 V at 1 V accuracy. Measure the DC electric field vector (DC-1 kHz) to monitor electrostatic acceleration structures and Alfvén waves that accelerate charged particles toward surface.</td><td>RPWI</td></tr><tr><td></td><td></td><td>CB.2g. In regions co-located with subsurface profiles: Acquire precise topography at 1 meter vertical resolution along-track at 100-meter (goal: a few tens of meters) horizontal resolution.</td><td>GALA</td></tr><tr><td></td><td></td><td>CB.2h. Measure subsurface dielectric properties in targeted regions by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth).</td><td>RIME</td></tr></tbody></table>
<table><caption>**Table 5** (Continued)</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td>CB.3</td><td>Characterize the ionosphere and exosphere of Callisto.</td><td>CB.3a. Identify and determine column densities of atmospheric species across the globe at 1 km spatial resolution or better using stellar occultations. Requires coverage in the wavelength ranges of 0.4 to 2.0 µm with spectral resolution better than or equal to 5 nm and 2.0 to 5.0 µm with a spectral resolution better than or equal to 10 nm. Obtain global, two-dimensional, spectral-spatial images at better than 50 km/px spatial resolution in the wavelength range of 0.1- to 5-microns to measure CO<sub>2</sub>, C, O, CO, O<sup>+</sup> and other species in absorption and/or emission. spectral resolution better than 10 nm for wavelengths greater than 1.0-micron. Map atmospheric emissions by scanning perpendicular to the limb from ~300 km above the surface to the surface of the satellite (at steps of 5 km). Requires measurements in the wavelength range 1.0 to 2.0 µm at better than or equal to 5 nm from and 2.0 to 5 µm at better than or equal to 10 nm.<br>CB.3b. Identify and determine column densities of atmospheric species across the globe at 1 km spatial resolution or better using stellar occultations. Requires coverage in the wavelength ranges of 100- to 200- nm at 1 nm spectral resolution. Obtain global, two-dimensional, spectral-spatial images at better than 50 km/px spatial resolution in the wavelength range of 100- to 200-nm to measure CO<sub>2</sub>, C, O, CO, O<sup>+</sup> and other species in absorption and/or emission. Requires spectral resolution of 2 nm. Map atmospheric emissions by scanning perpendicular to the limb from ~300 km above the surface to the surface of the satellite (at steps of 5 km). Requires measurements in the wavelength range of 100 to 200 nm at 2 nm spectral resolution.<br>CB.3c. Measure neutral exospheric composition with sufficient accuracy and to sufficient mass resolution to identify major volatile species with mixing ratios better than 1%. Determine positive ion spectrum of sputtered ions with M/ΔM ≥ 20. Determine the particle precipitation distribution by measuring (in-situ) the precipitating electrons and ions (major magnetospheric species) in the 10's eV to MeV energy range, and by imaging the sputtered and backscattered neutrals from the surface in the 10's eV to few keV range with an energy resolution ≤100% and angular resolution ≤7°.</td><td>MAJIS<br>UVS<br>PEP</td></tr></tbody></table>
<table><caption>**Table 5 (Continued)**</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>CB.3d. Determine the plasma density and temperature of the ionosphere, ion drift speeds (dynamics) in the ionosphere, and the electric field vector with accuracy better than 0.1 mV/m. Measure electron and ion density (10<sup>-4</sup>–10<sup>5</sup>/cm<sup>3</sup>) and electron temperature (0.01–100 eV), as well as the ion ram speed (&lt;200-km/s). Constrain ion temperature (0- to 20-eV). Determine the ionizing Extreme Ultraviolet flux. Determine the electric field vectors (near DC to 1.6 MHz). Determine the presence of suprathermal electrons and plasma inhomogeneities (dn/n, 0–10 kHz). Determine energy transport by Alfvén- and plasma waves between populations, by measuring the electric (DC-45 MHz) and magnetic field (0.1 Hz–20 kHz) vectors.</td><td>RPWI</td></tr><tr><td></td><td></td><td>CB.3e. Measure three-axis magnetic field components at 32 to 128 Hz with a resolution of 0.1 nT across multiple flybys at different orbital phases.</td><td>JMAG</td></tr><tr><td></td><td></td><td>CB.3f. Determine the distribution of water vapour in the atmosphere from water line observations in the 600 GHz band. Determine the hydrogen and oxygen isotopic ratios of water.</td><td>SWI</td></tr><tr><td></td><td></td><td>CB.3g. Characterize and map the ionosphere by performing radio occultations over as wide a range of longitude space as possible.</td><td>3GM</td></tr><tr><td rowspan="3">CC. Study the CC.1 past activity</td><td rowspan="3">Determine the formation and characteristics of tectonic and impact landforms.</td><td>CC.1a. Acquire precise topography at 1 m vertical resolution and better than 1 km horizontal resolution with selected targets at 100-meter (goal: a few tens of meters) horizontal resolution. In regions co-located with subsurface profiles: Acquire precise topography at 1 meter vertical resolution along-track at 100-meter horizontal resolution.</td><td>GALA</td></tr><tr><td>CC.1b. Characterize large parts of the surface at medium resolution (~100's m/px) in four spectral band passess (e.g. 0.4 µm, 0.67 µm, 0.76 µm, 1.0 µm) in the wavelength range of 350 nm to 1.0 µm. Requires solar illumination at mid-morning to mid-afternoon local times. Acquire high-resolution (better than 50 m/px) imaging of selected targets. Measure topography on the order of 0.5 km/px spatial scale and better than or equal to 50 meter vertical resolution over regions of high interest.</td><td>JANUS</td></tr><tr><td>CC.1c. Measure surface reflectance in the wavelength range from 0.4 to greater than or equal to 5 µm with spectral resolution better than or equal to 5 nm from 0.4 to 2.0 µm and better than or equal to 10 nm from 2.0 to greater than or equal to 5 µm and spatial resolution better than or equal to 20 km/px. Requires targeted high spatial/high spectral observations of important geologic units and terrain types.</td><td>MAJIS</td></tr></tbody></table>
<table><caption>**Table 5** (Continued)</caption><thead><tr><th>Objectives</th><th>Investigations</th><th>Measurement Requirements</th><th>Instruments</th></tr></thead><tbody><tr><td></td><td></td><td>CC.1d. Identify and locally characterize subsurface compositional horizons and structures by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from a minimum of ~50 meters to 1% of the target depth) to estimate subsurface dielectric properties and the density of buried scatterers in targeted regions.</td><td>RIME</td></tr><tr><td rowspan="4">CC.2</td><td rowspan="4">Investigate the interior of Callisto, with a special emphasis on its degree of differentiation.</td><td>CC.2a. Derive information on the static shape by measuring range to the surface during multiple fly-bys.</td><td>GALA</td></tr><tr><td>CC.2b. Image the limb for shape determination by acquiring multiple images at better than 1 km/px resolution. Perform astrometric determination of the rate of change of Callisto's orbit by acquiring multiple images of Callisto from a distance including background stars with a position accuracy of at least 1 km. Determine the mean spin pole direction (obliquity) to better than 1 km by developing a geodetic control network (~20 points) at a resolution better than 500 m/px.</td><td>JANUS</td></tr><tr><td>CC.2c. Determine the static gravity field at low order by measuring the range-rate from spacecraft tracking during multiple flybys to derive the 2nd degree gravity field and local potential anomalies. Requires range-rate measurements with an accuracy ~0.01 mm/s over 60 s integration time. If tracking is available for all the flybys, the gravity field may be estimated up to degree 3 and the Love number k<sub>2</sub> with an accuracy of 6E-2</td><td>3GM</td></tr><tr><td>CC.2d.</td><td></td></tr><tr><td rowspan="2">CC.3</td><td rowspan="2">Constrain global and regional surface ages.</td><td>CC.3a. High spatial resolution observations (better than or equal to 1 km/px) from 0.4 to 5 µm (spectral resolution: better than or equal to 5 nm from 0.4 to 2.0 µm, better than or equal to 10 nm from 2.0 to greater than or equal to 5 µm), with emphasis on the spectral differences between geologic features (multi-ring basins, craters) and the surrounding areas. Medium spatial resolution (better than or equal to 10 km/px) on large areas to map leading/trailing asymmetries.</td><td>MAJIS</td></tr><tr><td>CC.3b. Perform detailed morphological characterization of selected features through imaging at better than or equal 50 m/px spatial scale. Determine the distribution and morphology of impact craters by mapping in four colors (visible to near-IR) for large areas at scales ~400 m/px and in a single color at regional scales (~100 m/px) with near-uniform lighting conditions and solar phase angles less than or equal to 45 degrees.</td><td>JANUS</td></tr></tbody></table>
<table><caption>**Table 5** (Continued)</caption><thead><tr><td>Objectives</td><td>Investigations</td><td>Measurement Requirements</td><td>Instruments</td></tr></thead><tbody><tr><td></td><td></td><td>CC.3c. High spatial resolution observations (better than or equal to 1 km/px) from 0.1 to 0.2 micron (spectral resolution: ≤ 2 nm), with emphasis on the spectral differences between geologic features (multi-ring basins, craters) and the surrounding areas. Medium spatial resolution (better than or equal to 10 km/px) on large areas to map leading/trailing asymmetries.</td><td>UVS</td></tr><tr><td></td><td></td><td>CC.3d. Identify and locally characterize subsurface compositional horizons and structures by obtaining profiles of subsurface dielectric horizons and structures down to a few kms (maximum depth from 1 to 9 km depending on the crust properties and with vertical resolution ranging from ~50 meters to 1% of the target depth) to estimate subsurface dielectric properties and the density of buried scatterers in targeted regions.</td><td>RIME</td></tr><tr><td></td><td></td><td>CC.3e. In regions co-located with subsurface profiles: Acquire precise topography at 1 meter vertical resolution along-track at 100-meter (goal: a few tens of meters) horizontal resolution.</td><td>GALA</td></tr></tbody></table>

**Acknowledgements** The lead author dedicates this work to Harald Hoffmann (1957-2018), first chairman of the JUICE Working Group 2 (WG2). Harald coordinated the inputs coming from different JUICE instrument teams and drafted a first timeline of one Europa flyby, demonstrating the potential of JUICE in maximising the science return during a critical mission phase. It was a pleasure and a privilege for the entire WG2 group to work with him.

**Funding** Open access funding provided by Istituto Nazionale di Astrofisica within the CRUI-CARE Agreement. Federico Tosi, Alice Lucchetti, Francesca Bovolo, Emiliano D'Aversa, Alessandra Migliorini, Pasquale Palumbo, Giuseppe Piccioni, Paolo Tortora, Cecilia Tubiana, Francesca Zambon, Marco Zannoni, Lorenzo Bruzzone and Luciano Iess acknowledge support from the Italian Space Agency (ASI), implementation agreement ASI-INAF n. 2023-6-HH.0. Hans Huybrighs gratefully acknowledges financial support from Khalifa University's Space and Planetary Science Center (Abu Dhabi, UAE) under Grant no. KU-SPSC-8474000336. John Carter, Thibault Cavalié, Yves Langevin, Emmanuel Lellouch, François Poulet and Gabriel Tobie acknowledge support from the Centre National d'Études Spatiales (CNES), contract CNES-CNRS n° 180 117. Philippa Molyneux, Kurt Retherford and Randy Gladstone acknowledge NASA funding supporting the UVS team for ESA's JUICE mission. The work of Frank Postberg was supported by the European Research Council (ERC) by the Consolidator Grant 724908 Habitat-OASIS. Support of the JUICE Science Operations Center is gratefully acknowledged.

**Declarations**

**Competing Interests** The authors have no competing interests to declare that are relevant to the content of this article. Cecilia Tubiana, Claire Vallat and Olivier Witasse are Guest Editors of the collection "ESA's Jupiter Icy Moons Explorer (JUICE): Science, Payload, and Mission", but were not involved in the peer review of this article.

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## Authors and Affiliations

Federico Tosi¹ ID • Thomas Roatsch² ID • André Galli³ ID • Ernst Hauber² ID •

Alice Lucchetti⁴ ID • Philippa Molyneux⁵ ID • Katrin Stephan² ID • Nicholas Achilleos⁶ ID •

Francesca Bovolo⁷ ID • John Carter⁸ ID • Thibault Cavalié⁹,¹⁰ ID • Giuseppe Cimò¹¹ ID •

Emiliano D'Aversa¹ ID • Klaus Gwinner² ID • Paul Hartogh¹² ID • Hans Huybrighs¹³,¹⁴ ID •
Yves Langevin¹⁸ ID • Emmanuel Lellouch¹⁰ ID • Alessandra Migliorini¹ ID •

Pasquale Palumbo¹ ID • Giuseppe Piccioni¹ ID • Jeffrey J. Plaut¹⁵ ID •

Frank Postberg¹⁶ ID • François Poulet⁸ ID • Kurt Retherford⁵ ID • Ladislav Rezac¹² ID •

Lorenz Roth¹⁷ ID • Anezina Solomonidou¹⁸ ID • Gabriel Tobie¹⁹ ID • Paolo Tortora²⁰ ID •

Cecilia Tubiana¹ ID • Roland Wagner² ID • Eva Wiström²¹ ID • Peter Wurz³ ID •

Francesca Zambon¹ ID • Marco Zannoni²⁰ ID • Stas Barabash²² ID •

Lorenzo Bruzzone²³ ID • Michele Dougherty²⁴ ID • Randy Gladstone⁵ ID •

Leonid I. Gurvits¹¹,²⁵ ID • Hauke Hussmann² ID • Luciano Iess²⁶ ID •

Jan-Erik Wahlund²⁷ ID • Olivier Witasse²⁸ ID • Claire Vallat²⁹ ID • Rosario Lorente²⁹ ID •

<figure><img src="image_26.png" /></figure>

F. Tosi

federico.tosi@inaf.it

T. Roatsch

thomas.roatsch@dlr.de

A. Galli

andre.galli@unibe.ch

E. Hauber

Ernst.Hauber@dlr.de

A. Lucchetti

alice.lucchetti@inaf.it

P. Molyneux

philippa.molyneux@swri.org

K. Stephan

Katrin.Stephan@dlr.de

N. Achilleos

nicholas.achilleos@ucl.ac.uk

F. Bovolo

bovolo@fbk.eu

J. Carter

john.carter@ias.u-psud.fr

T. Cavalié

thibault.cavalie@u-bordeaux.fr

G. Cimò

cimo@jive.eu

E. D'Aversa

emiliano.daversa@inaf.it

K. Gwinner

Klaus.Gwinner@dlr.de

P. Hartogh

hartogh@mps.mpg.de

H. Huybrighs

hans@cp.dias.ie

Y. Langevin

yves.langevin@ias.u-psud.fr

E. Lellouch

Emmanuel.Lellouch@obspm.fr

A. Migliorini

alessandra.migliorini@inaf.it
P. Palumbo
pasquale.palumbo@inaf.it

G. Piccioni
giuseppe.piccioni@inaf.it

J.J. Plaut
jeffrey.j.plaut@jpl.nasa.gov

F. Postberg
francois.poulet@universite-paris-saclay.fr

F. Poulet
frank.postberg@fu-berlin.de

K. Retherford
kurt.retherford@swri.org

L. Rezac
rezac@mps.mpg.de

L. Roth
lorenzr@kth.se

A. Solomonidou
anezina.solomonidou@hsc.gov.gr

G. Tobie
Gabriel.Tobie@univ-nantes.fr

P. Tortora
paolo.tortora@unibo.it

C. Tubiana
cecilia.tubiana@inaf.it

R. Wagner
Roland.Wagner@dlr.de

E. Wirstrom
eva.wirstrom@chalmers.se

P. Wurz
peter.wurz@unibe.ch

F. Zambon
francesca.zambon@inaf.it

M. Zannoni
m.zannoni@unibo.it

S. Barabash
stas@irf.se

L. Bruzzone
lorenzo.bruzzone@unitn.it

M. Dougherty
m.dougherty@imperial.ac.uk

R. Gladstone
randy.gladstone@swri.org

L.I. Gurvits
lgurvits@jive.eu

H. Hussmann
Hauke.Hussmann@dlr.de

L. Iess
luciano.iess@uniroma1.it
J.-E. Wahlund

jwe@irfu.se

O. Witasse

Olivier.Witasse@esa.int

C. Vallat

Claire.Vallat@esa.int

R. Lorente

Rosario.Lorente@esa.int

1 Istituto Nazionale di Astrofisica – Istituto di Astrofisica e Planetologia Spaziali (INAF-IAPS), Rome, Italy

2 Institute of Planetary Research, German Aerospace Center (DLR), Berlin, Germany

3 University of Bern, Physics Institute, Space Research and Planetary Sciences, Bern, Switzerland

4 Istituto Nazionale di Astrofisica – Osservatorio Astronomico di Padova (INAF-OAPd), Padua, Italy

5 Southwest Research Institute, San Antonio, TX, USA

6 University College London, Department of Physics & Astronomy, London, UK

7 Fondazione Bruno Kessler (FBK), Center for Digital Society, Trento, Italy

8 Institut d'Astrophysique Spatiale (IAS), CNRS/Université Paris-Saclay, Orsay, France

9 Laboratoire d'Astrophysique de Bordeaux, Université de Bordeaux, CNRS, Pessac, France

10 LESIA, Observatoire de Paris, Meudon, France

11 Joint Institute for VLBI ERIC, Dwingeloo, The Netherlands

12 Max Planck Institute for Solar System Research, Göttingen, Germany

13 Khalifa University, Space and Planetary Science Center, Abu Dhabi, UAE

14 Dublin Institute for Advanced Studies (DIAS), School of Cosmic Physics, Dunsink Observatory, Dublin, Ireland

15 NASA Jet Propulsion Laboratory, Pasadena, CA, USA

16 Freie Universität Berlin, Department of Earth Sciences, Berlin, Germany

17 KTH Royal Institute of Technology, Division of Space and Plasma Physics, Stockholm, Sweden

18 Hellenic Space Center, Athens, Greece

19 Nantes Université, Laboratoire de Planétologie et Géosciences, Nantes, France

20 Università di Bologna, Department of Industrial Engineering (DIN), Forlì, Italy

21 Chalmers University of Technology, Onsala, Sweden

22 Swedish Institute of Space Physics, Kiruna, Sweden

23 Università degli Studi di Trento, Dipartimento di Ingegneria e Scienza dell'Informazione, Trento, Italy

24 Imperial College London, Department of Physics, London, UK

25 Delft University of Technology, Faculty of Aerospace Engineering, Delft, The Netherlands

26 Università degli Studi di Roma “La Sapienza”, Dipartimento di Ingegneria Meccanica e Aerospaziale (DIMA), Rome, Italy
27 Swedish Institute of Space Physics, Uppsala, Sweden

28 European Space Agency – European Space Research and Technology Centre (ESA-ESTEC), Noordwijk, The Netherlands

29 European Space Agency – European Space Astronomy Centre (ESA-ESAC), Madrid, Spain

<figure><img src="image_27.png" /></figure>