The Gas Giants (Jupiter, Saturn, Uranus, and Neptune) Pluto and Beyond The Outer Planets The Gas Giants (Jupiter, Saturn, Uranus, and Neptune) Pluto and Beyond

The Gas Giants Located outside the asteroid belt Much larger and more massive than terrestrial planets Much less dense than terrestrial planets Large size gives them huge amounts of gravity to retain gasses Even though the thick atmospheres of hydrogen and helium make it difficult for scientists to directly view the surface of the gas giants, they believe each planet probably has a core made of rock and metals All four gas giants have a ring system made of dust and icy debris

Jupiter Location: 5th planet from the sun Rotation: 9 hours 50 minutes Revolution: 12 years Temperature: -160°C (outer atmospheric layers) as high as 30,000 °C in core Its mass is more than 300 times that of Earth and is twice that of the other eight planets combined. Jupiter has 60 moons, 4 of which are large and several thin rings. Gravity: 2.54 times that of Earth Diameter: 11 times Earths Density: 24% of Earths

Jupiter’s Atmosphere Jupiter’s atmosphere is much like the suns; 92% hydrogen and helium, however when it formed, it did not have enough mass for nuclear fusion to begin and never became a star. The bands of color on Jupiter’s surface are most likely organic molecules mixed with ammonia, methane and water vapor. Jupiter’s rapid rotation causes the gasses to separate into bands

Weather and Storms on Jupiter Jupiter’s Great Red Spot is a giant rotating storm similar to a hurricane. This storm has been raging for several hundred years. The Galileo space probe measured wind speeds of up to 540 km/hr. Many storms occurring at once on Jupiter at all times, some small, and scientists believe the planets internal heat has a greater impact on the weather than the suns energy does.

Saturn Location: 6th planet from the sun Rotation: 10 hours 30 minutes Revolution 29.5 years Temperature: -176°C due to distance from sun Saturn is the least dense of all planets Saturn has at least 30 moons Titan is the largest moon; it is half the size of Earth Gravity: 1.07 times that of Earth’s Diameter: 9.4 times Earth’s Density: 13% of Earth’s Saturn’s atmosphere is almost entirely Hydrogen and Helium

Saturn’s Bands and Rings Saturn’s rings are 2 times its diameter. The rings are made of billions of dust and ice particles from comets or other bodies. The space probe Cassini was what scientists used to learn about Saturn and its large moon Titan

Uranus Location: 7th planet from the sun Rotation: 17 hours Revolution: 84 years Temperature: cloud top temp:-214°C center of core: 7,000°C Uranus has 24 moons It also has 11 rings Uranus is the 3rd largest planet Gravity: 91% of Earth’s Diameter: 4 times that of Earth’s Density: 24% of Earth’s Atmosphere mainly H and He

Uranus’s Rotation Most planets rotate with their axis perpendicular to their orbital planes as they revolve around the sun. Uranus’s axis is almost parallel to the plane of orbit Voyager 2 is the probe that made the discoveries about Uranus.

Neptune Location: 8th planet from the sun Rotation: 16 hours Revolution: 164 years Temperature: average cloud top -225°C Moons: at least 8 Rings: possibly 4 Gravity: 1.2 times that of Earth’s Diameter: 3.9 times that of Earth’s Density: 30% of Earth’s Images from Voyager 2 and the Hubble Space Telescope have helped scientists understand Neptune.

Neptune’s Atmosphere Made mostly of hydrogen, helium and methane. The white clouds are frozen methane Strong winds exceed 1,000 km/hr The Great Dark Spot: a storm the size of Earth appeared and disappeared on Neptune’s surface.

Pluto demoted Summer 2006, about 2,500 scientists met in Prague, Czechoslovakia to re-define what qualifies a celestial body as a planet. They came up with these: 1. It must be in orbit around the Sun. 2. It must be large enough that it takes on a nearly round shape. 3. It has cleared its orbit of other objects.

More on Pluto Pluto was automatically disqualified because its highly elliptical orbit overlaps with that of Neptune. Another critical blow for Pluto was the discovery three years ago of the object designated 2003 UB313 or also called Eris, because it is 3,000 km (1,864 miles) in diameter which is bigger than Pluto. Both Pluto and Eris will be called Dwarf Planets along with the biggest asteroid in the Solar System, Ceres which is found in the asteroid belt between Mars and Jupiter

Pluto’s Statistics Pluto and it’s moon Charon Location: Beyond Neptune, near the Kuiper Belt Rotation: 6.4 days Revolution: 248 years Temperature: -235°C Gravity: 1% of Earth’s Diameter: 20% of Earth’s Density: 32% of Earth’s Moon: Charon (1/2 Pluto’s size) Pluto and it’s moon Charon

Kuiper Belt and Sedna Kuiper Belt - A region of the solar system that is just beyond the orbit of Neptune and contains small bodies made mostly of ice. Sedna – a celestial body ¾ the size of Pluto and orbits 3 times farther than Pluto. Located beyond the Kuiper Belt

Exoplanets Planets that orbit other stars than our Sun Over 100 discovered Found due the gravitational effect they have on the stars they orbit. All exoplanets that have been identified are larger than Uranus

The New Solar System