2. b. a. Moons of Jupiter – total of 63 confirmed!

3. Inner moons closer to Jupiter than Io

4. Amalthea

5. Jupiter’s Galilean Satellites – Worlds of their own! IoEuropaGanymedeCallisto To Jupiter

6. Sizes of some of the Galilean satellites of Jupiter

7. Jupiter’s moon Io, volcanologically the most active body in our Solar System. 1.) Color - sulfur! 2.) Albedo - 63 % 3.) No impact craters - fresh surface 4.) Recent lava flows 5.) Numerous calderas 6.) Numerous active volcanoes, spewing out sulfur and silicate lava

8. Io

9. Voyager’s discovery of active volcanic plumes on Io

10. Views of Pele Plume: 1,300 km wide 600 km high

11. Limb view Plume shadow Plumes seen on limb and as shadows on surface

12. Long lava flows at Ra Patera > 100 km long

14. Lava flows on Io

17. Examples of lava lakes at Kilauea, 1988

18. Where does the heat come from on Io? Tidal heating from Jupiter, Europa and Ganymede

19. Iron-rich core Molten interior Thin silicate crust Interior of Io; density = 3.55 gm/cc

21. Jupiter’s Galilean Satellites – Worlds of their own! IoEuropaGanymedeCallisto To Jupiter

22. Europa: 3,138 km diameter; density 3.04 gm/cc

23. Ideas for a frozen interior for Europa

24. Ideas for a liquid interior for Europa

25. How do we get heat into the interior of Europa? Tidal heating. Europa is tugged towards Jupiter, but is also pulled away from Jupiter by Io, Ganymede and Callisto. Without tidal heating, Europa would look like Callisto.

27. Colored bands – fractures in ice crust

28. Multiple periods of fracturing

29. Topography of fractures on Europa

30. Some craters are found on Europa – but very young!

31. “Icebergs” on Europa suggest thin (5 – 20 km) crust

32. If there is volcanism on Europa, ice may be thin, so….. Model of hot interior of Europa Black smokers on Earth Tube worms on Earth’s ocean floor hint that similar life could evolve on Europa without sunlight

33. Ganymede: 5,262 km diameter; density 1.94 gm/cc (Mercury diameter = 4,880 km)

34. Light and dark terrain on Ganymede – long geologic history

35. Grooves on Ganymede – signs of surface movement similar to plate tectonics on Earth?

36. Grooved Terrain on Ganymede

38. Signs of comet impacts? Chains of craters with ejecta

39. Liquid water Magnetometer data give clue to interior of Ganymede Silicate lower mantle Ice crust Iron core

40. Callisto: Diameter 4,800 km, density 1.86 gm/cc

41. Thousands of craters at all scales on Callisto

42. Valhalla basin - ~600 km in diameter

43. Details of a “ring” of Valhalla Basin

44. Magnetometer data give clue to interior of Callisto Solid rock-ice Ice-rich outer layer

45. Relative ages of the surfaces of the Galilean Satellites: From left to right, from young to old.