Structures within our solar system.

1. “I repeat, all planet leave is cancelled. I've just had an unhappy love affair, so I don't see why anybody else should have a good time.”Prostetnic Vogon JeltzThe Hitchhiker's Guide to the Galaxy HW2 due on Thursday! (Questions in a minute) Reading: Chapter 11: Gas Giants Chapter 12: Rings, moons, dwarf planets.

2. Structures within our solar system. Terrestrial planet/moons: Thin atmosphere over rocky crust over rocky mantle, over rocky (perhaps a liquid region) core. Jupiter/Saturn: H atmosphere over liquid H interior, over liquid metalic H, over rocky core. Neptune/Uranus: H atmosphere over liquid/ice (solid) water/ammonia/methane interior (mantle) over rocky rocre.

3. Jupiter’s Structure: H clouds thickening to Liquid H, thickening to Liquid metallic H over a Rocky core.

4. Uranus' structure New for us! * Mostly hydrogen atmosphere. Methane clouds * liquid/ice mantle made of water/ammonia/methane * rocky silicate core (like Earth's mantle) Density = 1.3 g/cc

5. Densities (in g/cc): Rocky worlds: 3.5 – 5.5 (Terrestrial planets ~5) Gas Giants: 0.7 – 1.5

6. As we go further away from the Sun, the solar system gets colder and colder.

7. Uranus Like Jupiter and Saturn, its atmosphere is mostly made of hydrogen. But it's clouds are made of methane.

8. Uranus has at least 21 moons, but only 5 are of reasonable size.

9. Neptune

10. Neptune also has rings! The main ring is less than 50km wide!

11. Neptune's structure is identical to Uranus' of hydrogen of liquid/ice water/ammonia/methane of rock. Density = 1.6 g/cc

12. Neptune has 14 known moons.

13. Moons of the outer solar system.

14. (Warm interior) Icy moon structure Crust made mostly of water-ice. Underneath lies a vast liquid layer of water Rocky mantle. Rocky (iron) core. Densities ~ 2 g/cc depending on how much rock to water/ice. Density = 3.0 g/cc

15. (Cold interior) Icy moon structure Rock/ice mixture surface/mantle Rocky (iron-mix) core. Densities ~ 2 g/cc depending on how much rock to water/ice. Density = 3.0 g/cc

16. Densities (in g/cc): Rocky worlds: 3.5 – 5.5 (Terrestrial planets ~5) Gas Giants: 0.7 – 1.5 Icy moons: ~2-3

17. Structures within our solar system. Terrestrial planet/moons: Thin atmosphere over rocky crust over rocky mantle, over rocky (perhaps a liquid region) core. Jupiter/Saturn: H atmosphere over liquid H interior, over liquid metalic H, over rocky core. Neptunian (Uranus too): H atmosphere over liquid/ice water/ammonia/methane interior, over rocky core. Icy (warm interior) moon: Ice crust over liquid ocean over rocky mantle over rocky core. Icy (cold interior) moon: Ice/rock mixture crust/mantle over rocky core.

18. Jupiter's moons Io is slightly larger than our Moon while Callisto is about the same size as Mercury.Ganymede is 10% larger than Mercury! All of these moons are locked in synchronous rotation. Only one side ever faces Jupiter.

19. Jupiter's moons The orbital resonance ratios are 8:4:2 for Io, Europa, and Ganymede (and nearly 1 for Callisto). Orbital periods are 1.77, 3.55, 7.13, and 17 days.

20. Io, the innermost Galilean moon

23. Io, the innermost Galilean moon *Io is the most volcanically active body in the solar system! * There are no noticeable impact craters on Io. *The heating is generated by tidal forces. Io's orbit is elliptical because of a gravitational tug-of-war between Jupiter and Europa, the next large moon. This stretching and pulling heats Io's interior.

24. Io's structure (terrestrial) Io has 3 layers: a thin, brittle crust, a thick, molten mantle, and a solid, core made mostly of iron. Density= 3.5 g/cc

25. Io's atmosphere Io has a thin, SO2 atmosphere. Some freezes out on the night side and evaporates on the day side. Jupiter's magnetic field sweeps material off of Io and into a doughnut-shaped cloud of intense radiation.

26. Europa

28. color-enhanced to show the lines better

29. Europa Also caught in a tug-of-war between massive Jupiter and other large moons, Europa has a fairly young surface, with only a few impact craters.

30. Europa's structure (warm icy moon) Europa has a thin (3 miles thick) crust made mostly of water-ice. Underneath lies a vast liquid layer of water, perhaps 30 miles thick. But most of the moon is made of rock, with perhaps an iron core. Density = 3.0 g/cc Europa has a thin, Oxygen atmosphere created by charged particles hitting the surface. Comparable to Earth's atmosphere at an altitude of over 100 miles!

31. Europa has a vast under-crust ocean. Kept liquid by volcanic vents.

32. Ganymede

33. Ganymede As we move out from Jupiter, the tidal flexing becomes less, and the surfaces get colder and older. Ganymede is the largest moon in the solar system and also generates it's own magnetic field, just like the Earth!

34. Ganymede's structure (warm icy moon) Like Europa, Ganymede has a thin, mostly ice crust. Underneath is a thick, water-ice layer (mostly frozen). Under that is a rocky mantle surrounding an iron core. Density = 1.9 g/cc Like Europa, Ganymede has an extremely thin Oxygen atmosphere created by charged particles hitting the ice surface.

35. Callisto Callisto's surface is old and heavily cratered.

36. Callisto's structure Being the furthest moon from Jupiter and under the least tidal stress, Callisto did not have time to differentiate much before it became frozen. Density = 1.9 g/cc However, Callisto shows signs of a variable magnetic field, an indication of a subterranean, salty ocean.

37. Older & colder the farther away from Jupiter. Io < few million, Europa ~20-180 million years, Ganymede ~3 billion years, Callisto: 4-4.5 billion years old

38. Structure changes as they get further from Jupiter. Surface Age: Io < few million Europa ~20-180 million years Ganymede ~3 billion years Callisto: 4-4.5 billion years old Density = 3.5 g/cc Density = 3.0 g/cc Density = 1.9 g/cc Density = 1.8 g/cc

39. Jupiter also has lots of smaller, irregular moons. Jupiter has 67 moons in total.

41. Turn in 1 paper per group only. Write legibly, make sure everyone’s name (first and last) are on it. Names on top, group ‘symbol’ beneath. No resources- keep phones/laptops/tablets put away or your group will lose their paper and receive a 0. Group yourselves up! No more than 4, no less than 3 people. Papers with <3 or >4 students will not be graded.

42. 1 Saturn’s moon Titan. At 10AU from the Sun, the temperature in space is -290oF. Bigger than our Moon. List 2 observations from this image. We see ____ it means ___.

43. Infrared image. Just treat it like a black and white image. List 2 more observations. 2

44. 3 3 observations & meanings

45. 4 Estimate surface age and list 2 erosive processes or put ‘no erosion’

46. 300 miles across. 2 obs & meanings 5

47. 6 Carefullly examine the area within the arrows. What is this feature and what does it mean to the object as a whole? (2 things) Image is ~200 miles across.

48. 7 Huygens optical picture while parachuting down. What are we looking at and what does it mean to the environment of this moon?

49. 8 True color image from the surface. List 2 observations and their meanings.

50. Artist's recreation of the landing site.