1. Characterize the morphology, geology, and physical state of the satellite surfaces
2. Investigate the satellites surface mineralogy and determine the distribution of the compositional units
3. Determine the satellites gravitational fields, magnetic fields and dynamic properties
4. Study satellite atmospheres and ionospheres, extended gas clouds arising from the satellites, and interactions with the magnetosphere

1. Geological evolution of Io and Europa (samples < 1 km)
2. Geological evolution of Ganymede and Callisto (samples < 100 m)
3. Nature of current Io volcanism/variability
   (target plumes, surface flows, frosts, dark side search for silicate volcanism)
4. Global context for #1.
   (Europa moderate resolution regional coverage - some with color)
5. Global context for #2.
   (regional moderate resolution < 2km - some with color)
6. Global context for #2 (Callisto color samples)
7. Surface composition of all satellites (photometric properties of all)
8. Origin and mass balance of ring material
9. Additional regional Callisto coverage (< 2km)
10. Voyager complimentary coverage in color (to extent possible)

• Volcanism
  
• Tectonism
  
• Ice as a Rock
  
• Mass Wasting
  

Ganymede

• Science Objectives
  Ganymede was well imaged by Voyager so most resources are devoted to high resolution observations.
  1. Characterize any volcanism
  2. Determine the nature and timing of any tectonic activity
  3. Determine the history of formation and degradation of impact craters
  4. Determine the nature of the surface materials
  
  
• Features and Processes
  • dark terrain
  • light terrain
  • palimpsest
  • ice-volcanic melts
  • viscous relaxation
  • mass wasting

• Image Sequence
  • Orbit G1
    Geodetic Control
    Color Global
    Uruk Sulcus
    Galileo Regio
    Memphis Facula
    Unnamed Sulcus
    
  • Orbit G2
    Light/Dark Boundary (134 kb)
    Dark Floor Crater (103 kb)
    Galileo Regio Furrows (101 kb)
    Dark Grooves (148 kb)
    Groove Lanes (228 kb)
    Nippur Sulcus (126 kb)
    Palimpsest (189 kb)
    Uruk Sulcus (270 kb)
    Transitional Terrain (144 kb)

Callisto

• Science Objectives
  1. Acquiring high resolution samples of typical cratered terrain and components of the Valhalla and Asgaard basins
  2. Filling Voyager gaps
  3. Color sampling of the surface at local, regional, and global scales
  4. Determining the surfaces photometric properties
  
  
• Features and Processes

• Image Sequence
  • Orbit G2
    Voyager Gap Fill (93kb)
    
  • Orbit C3
    Asgard Ring Structure (121kb)
    Global Color (126kb)
    High Resolution of Valhalla Region (139kb)
    Voyager Gap Fill (127kb)
    
  (New images beginning September 1996)

Europa

• Science Objectives
  Europa was poorly imaged by Voyager so the plan includes a mix of high resolution and low resolution observations to provide context.
  1. Determine the nature, origin, and age of the tectonic features
  2. Determine the nature, rates and sequence of resurfacing events
  3. Assess the cratering history
  4. Map spectral and photometric properties
  
  
• Features and Processes

• Image Sequence
  • Orbit G1
    Global and North Pole Color
    
  • Orbit C3
    Global Context (51kb)
    Near Terminator Morphologies (105kb)
    
  • Orbit E4
    Global Mapping (86kb)
    Regional and High Resolution of Maculae and Dark Material (101kb)
  (New images beginning July 1996)

Io

• Science Objectives
  1. Near terminator mapping of topography at 2-10 km resolution
  2. Monitor color and albedo changes of the surface
  3. Monitor plume activity
  
  
• Features and Processes

• Image Sequence
  (New images beginning July 1996)

The complete Image Guide text for all of the images

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Last updated: June 28, 1996, by Ross Beyer