Lesson 3: The Outer Planets – Jupiter: We learned about the outer planets which are made of materials that are usually gases on Earth so we refer to them as gas giants. Gravitational forces produced by the large sizes of these planets change gases into a liquids. Jupiter is the largest planet in the solar system. Although it takes 12 years to revolve around the Sun, Jupiter rotates faster than any other planet. Jupiter has a system of rings around it. The atmosphere contains helium but is mostly made of hydrogen. Jupiter’s rotation stretches its clouds into colorful bands. The Great Red Spot on Jupiter is a storm that has lasted more than 300 years. Jupiter’s entire structure is made up of about 80% hydrogen and about 20% helium. It has a solid core that is surrounded by liquid hydrogen. The four largest moons of Jupiter are called Galilean moons. These are Io, Europa, Ganymede, and Callisto. Lesson 3: The Outer Planets – Saturn, Uranus, and Neptune: We learned that Saturn rotates rapidly and has clouds in bands. It is mostly made of hydrogen and helium and has the largest ring system in the solar system. Saturn has seven bands of rings, each of which contains thousands of smaller rings made mainly of ice particles. Most of Saturn’s moons are small, but one of them, Titan, is larger than the planet Mercury. We learned that Uranus’s atmosphere contains mostly hydrogen and helium with small amounts of methane. Beneath Uranus’s atmosphere is a slushy layer of water, ammonia, and other materials. Then we learned that Uranus might have a rocky core. Next we learned that the rotational axis of Uranus is tilted more than that of any other planet. It has at least 27 moons and a small ring system. The atmosphere and interior of Neptune are similar to Uranus. Neptune has at least 13 moons and a faint ring system.
Assignment: Create Venn diagrams comparing and contrasting the 4 outer planets.
Discussion Question:
Compared to the inner planets, why are outer planets more likely to have rings around them?
The outer planets are so massive that they have very strong gravitational forces. These forces apply tremendous pressure on the atmosphere of each planet. If a moon from one of these planets shattered, its pieces would remain in orbit around the planet, forming a ring.