Presentation on theme: "Jupiter. 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."— Presentation transcript:
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?
When and where can you see it? Fourth brightest object in the sky (behind the Sun, moon, and Venus).
Physical Properties Mass: 1.9 x kg or 318 Earth masses. Has more than twice the mass of all the other planets combined. Still, it is only a 1000 th 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.
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
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.
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.)
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.
Reading on pg. 284 Almost a star?
Jupiter’s Magnetosphere Jupiter has a huge magnetosphere that extends all the way out to Saturn! This results in aurorae.
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.
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.
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.
Another interesting point (to me)! The orbital periods of the four Galilean satellites are in the ratio of 1:2:4:8.
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.
Europa: Land of Ice Contains few craters. Is likely covered by an ocean that is frozen over. This water could possibly harbor life (marine).
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.
Jupiter’s Ring Discovered by Voyager in Very small. Could be a result of meteoric impact on two of Jupiter’s small moons.