1. The Jovian Planets The Gas Monsters.

2. Jupiter

3. Size of Jupiter Jupiter is the fifth planet from the Sun and by far the largest. Jupiter is more than twice as massive as all the other planets combined (318 times Earth). Jupiter is the fifth planet from the Sun and by far the largest. Jupiter is more than twice as massive as all the other planets combined (318 times Earth). Orbit: 778,330,000 km (5.20 AU) from Sun Diameter: 142,984 km (equatorial) Mass: 1.900e27 kg

4. Mythology Jupiter (a.k.a. Jove; Greek Zeus) was the King of the Gods, the ruler of Olympus and the patron of the Roman state. Zeus was the son of Cronus (Saturn). Jupiter (a.k.a. Jove; Greek Zeus) was the King of the Gods, the ruler of Olympus and the patron of the Roman state. Zeus was the son of Cronus (Saturn).

5. Composition The gas planets do not have solid surfaces, their gaseous material simply gets denser with depth. The gas planets do not have solid surfaces, their gaseous material simply gets denser with depth.

6. Composition Jupiter is about 90% hydrogen and 10% helium with traces of methane, water, ammonia and "rock". Jupiter is about 90% hydrogen and 10% helium with traces of methane, water, ammonia and "rock".

7. Jupiter and the other gas planets have high velocity winds which are confined in wide bands of latitude. Jupiter and the other gas planets have high velocity winds which are confined in wide bands of latitude. The winds blow in opposite directions in adjacent bands. The winds blow in opposite directions in adjacent bands. Slight chemical and temperature differences between these bands are responsible for the colored bands that dominate the planet's appearance. Slight chemical and temperature differences between these bands are responsible for the colored bands that dominate the planet's appearance. The light colored bands are called zones; the dark ones belts. The light colored bands are called zones; the dark ones belts.

8. Atmospheric Belts and Zones

9. Atmosphere The interior heat of Jupiter probably causes convection deep within Jupiter's liquid layers and is probably responsible for the complex motions we see in the cloud tops. The interior heat of Jupiter probably causes convection deep within Jupiter's liquid layers and is probably responsible for the complex motions we see in the cloud tops.

10. Voyager Space Craft Voyager Space Craft The voyager space crafts have given us much of the information we know about Jupiter and Saturn The voyager space crafts have given us much of the information we know about Jupiter and Saturn

11. Clouds and Spots

12. The Great Red Spot

13. GRS The Great Red Spot (GRS) has been observed from Earth for more than 300 years The Great Red Spot (GRS) has been observed from Earth for more than 300 years The GRS is an oval about 12,000 by 25,000 km, big enough to hold two Earths. Other smaller but similar spots have been known for decades.

14. Interior of Jupiter

15. Metallic Hydrogen? Metallic Hydrogen?

16. IMPACT! In July 1994, Comet Shoemaker-Levy 9 collided with Jupiter with spectacular results In July 1994, Comet Shoemaker-Levy 9 collided with Jupiter with spectacular results

17. Jupiter has rings like Saturn's, but much fainter and smaller (right). They were totally unexpected and were only discovered when two of the Voyager 1 scientists insisted that after traveling 1 billion km it was at least worth a quick look to see if any rings might be present

18. Moons Galileo's discovery, in 1610, of Jupiter's four large moons Io, Europa, Ganymede and Callisto, are now known as the Galilean moons). Galileo's discovery, in 1610, of Jupiter's four large moons Io, Europa, Ganymede and Callisto, are now known as the Galilean moons). Jupiter has 16 known satellites, the four large Galilean moons and 12 small ones Jupiter has 16 known satellites, the four large Galilean moons and 12 small ones

19. Saturn

20. Mythology In Roman mythology, Saturn is the god of agriculture. In Roman mythology, Saturn is the god of agriculture. The associated Greek god, Coronus, was the son of Uranus and Gaia and the father of Zeus (Jupiter). The associated Greek god, Coronus, was the son of Uranus and Gaia and the father of Zeus (Jupiter). Saturn is the root of the English word "Saturday" Saturn is the root of the English word "Saturday"

21. Mass, Size, and Distance M =6.58 x 10 26 kg M =6.58 x 10 26 kg Diameter = 119,000 km equatorial and 107,000 polar. Diameter = 119,000 km equatorial and 107,000 polar. Distance to sun = 9.52 AU or 1,426,000,000 km Distance to sun = 9.52 AU or 1,426,000,000 km

22. Orbit Saturn’s orbit is almost spherical. Saturn’s orbit is almost spherical. The planet is inclined about 27 degrees from vertical. The planet is inclined about 27 degrees from vertical.

23. Composition Like Jupiter, Saturn is about 75% hydrogen and 25% helium with traces of water, methane, ammonia and "rock Like Jupiter, Saturn is about 75% hydrogen and 25% helium with traces of water, methane, ammonia and "rock

24. Saturn’s Interior

25. Saturn’s Rings

26. Ring Composition The rings are actually composed of innumerable small particles each in an independent orbit. The rings are actually composed of innumerable small particles each in an independent orbit. They range in size from a centimeter or so to several meters. They range in size from a centimeter or so to several meters. A few kilometer-sized objects are also likely. A few kilometer-sized objects are also likely.

27. Close-up of rings

28. Moons—15!

29. Titan Second largest moon in the Solar System Second largest moon in the Solar System

30. TITAN IS THE ONLY MOON TO HAVE A KNOWN ATMOSPHERE TITAN IS THE ONLY MOON TO HAVE A KNOWN ATMOSPHERE

31. Uranus

32. Mythology Uranus is the ancient Greek deity of the Heavens, the earliest supreme god. Uranus is the ancient Greek deity of the Heavens, the earliest supreme god.

33. Size, Mass, Distance orbit: 2,870,990,000 km (19.218 AU) from Sun orbit: 2,870,990,000 km (19.218 AU) from Sun diameter: 51,118 km (equatorial) diameter: 51,118 km (equatorial) mass: 8.683 x 10 25 kg mass: 8.683 x 10 25 kg

34. Uranus from Earth Uranus was the first planet discovered in modern times (March 13, 1781).

35. Composition Uranus is composed primarily of rock and various ices, with only about 15% hydrogen and a little helium (in contrast to Jupiter and Saturn which are mostly hydrogen). Uranus is composed primarily of rock and various ices, with only about 15% hydrogen and a little helium (in contrast to Jupiter and Saturn which are mostly hydrogen). Uranus (and Neptune) are in many ways similar to the cores of Jupiter and Saturn minus the massive liquid metallic hydrogen envelope. Uranus (and Neptune) are in many ways similar to the cores of Jupiter and Saturn minus the massive liquid metallic hydrogen envelope. It appears that Uranus does not have a rocky core like Jupiter and Saturn but rather that its material is more or less uniformly distributed. It appears that Uranus does not have a rocky core like Jupiter and Saturn but rather that its material is more or less uniformly distributed.

36. Atmosphere Uranus' atmosphere is about 83% hydrogen, 15% helium and 2% methane. Uranus' atmosphere is about 83% hydrogen, 15% helium and 2% methane.

37. Rotation of Uranus Most of the planets spin on an axis nearly perpendicular to the plane of the ecliptic but Uranus' axis is almost parallel to the ecliptic. Most of the planets spin on an axis nearly perpendicular to the plane of the ecliptic but Uranus' axis is almost parallel to the ecliptic. At the time of Voyager 2's passage, Uranus' south pole was pointed almost directly at the Sun. At the time of Voyager 2's passage, Uranus' south pole was pointed almost directly at the Sun. This results in the odd fact that Uranus‘ polar regions receive more energy input from the Sun than do its equatorial regions. This results in the odd fact that Uranus‘ polar regions receive more energy input from the Sun than do its equatorial regions.

38. Rings Like the other gas planets, Uranus has rings. Like the other gas planets, Uranus has rings. Like Jupiter's, they are very dark but like Saturn's they are composed of fairly large particles ranging up to 10 meters in diameter in addition to fine dust. Like Jupiter's, they are very dark but like Saturn's they are composed of fairly large particles ranging up to 10 meters in diameter in addition to fine dust. There are 11 known rings, all very faint; the brightest is known as the Epsilon ring. There are 11 known rings, all very faint; the brightest is known as the Epsilon ring.

39. Moons Uranus has 20 named moons plus 1 recently discovered one which as yet has not been given an official name. Unlike the other bodies in the solar system which have names from classical mythology, Uranus' moons take their names from the writings of Shakespeare and Pope.

40. Neptune

41. Mythology In Roman mythology Neptune (Greek: Poseidon) was the god of the Sea. In Roman mythology Neptune (Greek: Poseidon) was the god of the Sea.

42. Discovery of Neptune After the discovery of Uranus, it was noticed that its orbit was not as it should be in accordance with Newton's laws. It was therefore predicted that another more distant planet must be perturbing Uranus' orbit. Neptune was first observed by Galle and d'Arrest on 1846 Sept 23 very near to the locations independently predicted by Adams and Le Verrier from calculations based on the observed positions of Jupiter, Saturn and Uranus. After the discovery of Uranus, it was noticed that its orbit was not as it should be in accordance with Newton's laws. It was therefore predicted that another more distant planet must be perturbing Uranus' orbit. Neptune was first observed by Galle and d'Arrest on 1846 Sept 23 very near to the locations independently predicted by Adams and Le Verrier from calculations based on the observed positions of Jupiter, Saturn and Uranus.

43. Orbit, Mass, Diameter orbit: 4,504,000,000 km (30.06 AU) from Sun diameter: 49,532 km (equatorial) mass: 1.0247e26 kg orbit: 4,504,000,000 km (30.06 AU) from Sun diameter: 49,532 km (equatorial) mass: 1.0247e26 kg

44. Composition Neptune's composition is probably similar to Uranus': various "ices" and rock with about 15% hydrogen and a little helium. Neptune's composition is probably similar to Uranus': various "ices" and rock with about 15% hydrogen and a little helium. Like Uranus, but unlike Jupiter and Saturn, it may not have a distinct internal layering but rather to be more or less uniform in composition. But there is most likely a small core (about the mass of the Earth) of rocky material. Like Uranus, but unlike Jupiter and Saturn, it may not have a distinct internal layering but rather to be more or less uniform in composition. But there is most likely a small core (about the mass of the Earth) of rocky material. Its atmosphere is mostly hydrogen and helium with a small amount of methane. Its atmosphere is mostly hydrogen and helium with a small amount of methane.

45. Atmosphere Like a typical gas planet, Neptune has rapid winds confined to bands of latitude and large storms or vortices. Neptune's winds are the fastest in the solar system, reaching 2000 km/hour. Like a typical gas planet, Neptune has rapid winds confined to bands of latitude and large storms or vortices. Neptune's winds are the fastest in the solar system, reaching 2000 km/hour.

46. Rings Neptune also has rings. Earth-based observations showed only faint arcs instead of complete rings, but Voyager 2's images showed them to be complete rings with bright clumps. Neptune also has rings. Earth-based observations showed only faint arcs instead of complete rings, but Voyager 2's images showed them to be complete rings with bright clumps.

47. Because Pluto's orbit is so eccentric, it sometimes crosses the orbit of Neptune making Neptune the most distant planet from the Sun for a few years.

48. Moons Neptune has 8 known moons; 7 small ones and Triton. Neptune has 8 known moons; 7 small ones and Triton.

49. Pluto

50. Mythology In Roman mythology, Pluto (Greek: Hades) is the god of the underworld. The planet received this name (after many other suggestions) perhaps because it's so far from the Sun that it is in perpetual darkness and perhaps because "PL" are the initials of Percival Lowell. Lowell predicted the existence of Pluto

51. Pluto was discovered in 1930 by a fortunate accident. Calculations which later turned out to be in error had predicted a planet beyond Neptune, based on the motions of Uranus and Neptune. Not knowing of the error, Clyde W. Tombaugh at Lowell Observatory in Arizona did a very careful sky survey which turned up Pluto anyway.

52. Mass, Size, Distance orbit: 5,913,520,000 km (39.5 AU) from the Sun (average) diameter: 2274 km mass: 1.27 x 10 22 kg

53. Orbit Pluto's orbit is highly eccentric. At times it is closer to the Sun than Neptune (as it was from January 1979 thru February 11 1999). Pluto rotates in the opposite direction from most of the other planets.

54. PLUTO FROM EARTH BASED TELESCOPE

55. Composition Pluto's composition is unknown, but its density (about 2 gm/cm3) indicates that it is probably a mixture of 70% rock and 30% water ice much like Triton. The bright areas of the surface seem to be covered with ices of nitrogen with smaller amounts of (solid) methane, ethane and carbon monoxide.

56. Moons Fortunately, Pluto has a satellite, Charon. By good fortune, Charon was discovered (in 1978) just before its orbital plane moved edge-on toward the inner solar system. It was therefore possible to observe many transits of Pluto over Charon and vice versa. By carefully calculating which portions of which body would be covered at what times, and watching brightness curves, astronomers were able to construct a rough map of light and dark areas on both bodies.

57. Pluto and Charon from HST