Jovian Planets

2. Jovian Planets Solar System Part 2

3. Jovian Planets • Overview: • In this chapter we will look at the large jovian planets and some of the stuff left from the formation of the solar system. • Objectives: •  1. To know the characteristics that distinguish the jovian planets, Jupiter, Saturn, Neptune and Uranus. • 2. To examine what is known of the final planet called Pluto. • 3. To examine the asteroid belt. • 4. To explain comets and their origins.

4. Jovian Planets • I. Jupiter • A. Orbit • 1. Jupiter is the closest of the jovian planets, with an orbit that takes it about 5 astronomical units from the sun. • 2. This gives the planet a year equivalent to 11.9 Earth years. http://science.discovery.com/video-topics/space-videos/space-school-jupiter.htm#/space-school-jupiter.htm

5. Jovian Planets • B. Size - Big, just big. • 1. Jupiter has a radius of 71,400 km. • 2. It would take about 1400 Earths to fill Jupiter.

6. Jovian Planets • C. Composition • 1. Surprisingly, considering the size, its' density is only ~1 g/cm3 compared with Earth's ~5 g/cm3 . • 2. Jupiter is primarily hydrogen (86%) and helium (13.8%). • 3. The rest is methane, ammonia, and water found mostly in the high atmosphere clouds.

7. Jovian Planets • D. Rotation • 1. Differential Rotation - Since Jupiter has no solid surface the planet is free to rotate at different rates at the equator and the pole. • 2. Near the equator Jupiter rotates once every 9 hours and 56 minutes making it the fastest rotational body in the solar system.

8. Jovian Planets • 3. At the poles the it rotates once every 9 hours and 50 minutes producing a magnetic field 20,000 times greater than the Earth's.

9. Jovian Planets • E. Atmosphere • 1. Battle of the Bands • a. The light bands across the planet are called zones and represent areas where warm material is rising in a convection current.

10. Jovian Planets • b. The dark bands are called belts and are areas where cooler material is sinking in these convection currents.

11. Jovian Planets • 2. Great Red Spot • a. The most prominent feature of Jupiter is the giant circulating storm system near the equator nearly ~25,000 km in length. • b. The spot is known to have existed since it was first reported 300 years ago.

12. Jovian Planets • F. Moons - Jupiter has at least 67 moons ranging from Leda only 15 km across to Ganymeade at 5260 km. http://www.space.com/18400-jupiter-s-moons-some-icy-some-volcanic-and-some-larger-than-our-moon-video.html

13. Jovian Planets • 1. Io • a. Io is the most geologically active object in the solar system. • b. Due to the tidal heating caused by Jupiters gravity Io has huge volcanoes that spew sulfur compounds, which color the surface orange. • (loki – volcano on Jupiter) • innermost of the four Galilean moons of the planet Jupiter and, with a diameter of 3,642 kilometres, the fourth-largest moon in the Solar System.

14. Jovian Planets • 2. Europa • a. Europa is a relatively smooth moon with a cracked ice surface. • b. It is possible that a liquid ocean warmed by the tidal forces of Jupiter is below this cracked exterior. • c. Many speculate this moon may be our best chance to find life.

15. Jovian Planets • G. Ring - Voyager found a faint ring of dark dust and rock about 50,000 km above the planets cloud cover

16. Jovian Planets • II. Saturn • A. Orbit • 1. Saturn's orbit extends out to 9.5 astronomical units • 2. At this distance Saturn's revolutionary period is ~29.5 Earth years. • B. Size - Saturn has a radius of 60,000 km. http://science.discovery.com/video-topics/space-videos/space-school-saturn.htm#/space-school-saturn.htm

17. Jovian Planets • C. Composition • 1. Saturn , like Jupiter, is mostly hydrogen (92 %) and helium (7%) • 2. The rest is ammonia and methane.

18. Jovian Planets • D. Rotation • 1. Saturn rotates every 10 hours and 14 minutes at the equator and 10 hours and forty minutes at the pole. • 2. This differential rotation produces a large magnetic field and a flattening of the poles. • 3. Saturn is tilted 27 degrees, although solar heating isn't as important this far out so there aren't any noticeable seasons.

19. Jovian Planets • E. Atmosphere • 1. Similar to Jupiter, Saturn has alternating bands of gas layers forming convection currents. • 2. The cloud cover is much thicker on Saturn and dominated by ammonia giving it a butterscotch color.

20. Jovian Planets • F. Rings - The most prominent feature of Saturn is the intricate ring system that spans ~200,000 km in diameter.

21. Jovian Planets • a. The rings consist of millions of individual chunks ranging from a few millimeters to several tens of meters in diameter. • b. The major substance that makes up these pieces is water ice.

22. Jovian Planets • 1. Where did they come from? • a. As an orbiting body comes closer to a large source of gravity it experiences larger and larger tidal effects. • b. At a point called the Roch limit the internal forces holding the object together are overcome by the tidal forces ripping it apart and presto : little pieces.

23. Jovian Planets • G. Moons • a. Saturn has ~18 moons ranging from Pan ~20 km across to Titan ~5150 km , near the size of the Moon. • b. Titan is unique with a thick atmosphere of nitrogen even denser than the atmosphere of Earth.

24. Jovian Planets • c. Mimas is a medium sized moon with a proportionally huge crater called Herschel.