Jupiter

1. Jupiter

2. Jupiter

3. Interesting note…at least to me! • The ancient Greeks did not know how big Jupiter was…and Venus appeared brighter. • So why did they name it after the most powerful god?

4. When and where can you see it? • Fourth brightest object in the sky (behind the Sun, moon, and Venus).

5. Physical Properties • Mass: 1.9 x 1027 kg or 318 Earth masses. • Has more than twice the mass of all the other planets combined. • Still, it is only a 1000th the mass of the Sun. • Its radius is 11.2 Earth radii. More than 1400 Earth’s would fit inside! • It orbits 5.20 AU’s from the sun. • Has no orbital tilt, therefore no seasons.

6. Rotation Rates • Jupiter experiences differential rotation. Because it is gaseous, not all parts orbit at the same rate! • Rate of rotation: 9 hours, 55 min • Spinning this fast gives is an equatorial bulge. • Rate of revolution: 11.9 Earth years

7. Atmosphere • Is dominated by atmospheric bands and the Great Red Spot. • The bands are areas of low pressure or high pressure. • The colors are based on complex chemical reactions occurring in the bands. • Some simple organic molecules (ethane) have been detected in the clouds.

8. What is beneath the clouds? • Well, more gases. This would be considered to be the interior of the planet. • Temperature and density increases with depth. • Eventually the gas becomes a liquid. • Further down this liquid hydrogen becomes metallic! • Finally, there is a small extremely dense solid core (may contain between 5-20 Earth masses.)

9. Weather on Jupiter • The Great Red Spot averages twice the diameter of Earth. • Flashes resembling lightning have been detected. • White ovals depict storm systems. • Brown ovals depict holes in the clouds that allow for looks down into the lower atmosphere.

11. Reading on pg. 284 • Almost a star?

12. Jupiter’s Magnetosphere • Jupiter has a huge magnetosphere that extends all the way out to Saturn! • This results in aurorae.

14. Jupiter as a heat source • Jupiter gives off more heat itself than it receives from the sun. • Why? • Some is due to radioactive decay, just as in the Earth. • However, most is residual heat from its formation.

15. Moons of Jupiter • The current count is 63. • The largest 16 are 10 km or bigger. • The four largest, the Galilean satellites are Io, Europa, Ganymede and Callisto, are named after the mythological attendants of Jupiter. • Some are locked in synchronous orbit with Jupiter, due to tidal forces.

16. Moons of Jupiter, cont. • Some of the smaller moons orbit very eccentrically. • Some revolve in a retrograde direction. • These smaller ones may have at one time been part of a larger object that broke apart after being captured by Jupiter’s gravity.

19. Another interesting point (to me)! • The orbital periods of the four Galilean satellites are in the ratio of 1:2:4:8.

21. Io: Land of Volcanoes • Very dense • Geologically active - due to tidal forces from Jupiter and the other Galilean satellites. • More than 80 active volcanoes have been discovered. • The largest one is Loki – larger than the state of Maryland and emits more energy than all of Earth’s volcanoes combined. • It’s mass and radius are similar to Earth’s moon.

24. Europa: Land of Ice • Contains few craters. • Is likely covered by an ocean that is frozen over. • This water could possibly harbor life (marine).

27. Ganymede and Callisto: Twins? • Ganymede is the largest moon in the solar system (bigger than Pluto and Mercury). • Ganymede has maria. • Ganymede used to have plate tectonics. • Callisto is home to a large basin called Valhalla. • Callisto shows no evidence of plate tectonics. • It may have a layer of slush ice beneath its surface.

31. Jupiter’s Ring • Discovered by Voyager in 1979. • Very small. • Could be a result of meteoric impact on two of Jupiter’s small moons.