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Outside the window, huge chunks of rock flew past. Some were as big as mountains, and many passed within a few feet of the ship. Dara said, "If even one of those crashed into us . . ."
SAM interrupted, "The programmed trajectory is safe. This asteroid belt is a band of hundreds of thousands of large and small rocks in orbit around the Sun. The belt marks the boundary between the Inner and Outer Planets.
"We approach Jupiter, the first of the Outer Planets. It is the largest planet in our solar system, with a diameter of 88,700 mi (142,700 km). It is more than 1,000 times the size of Earth and is 484,000,000 mi (778,000,000 km) from the Sun. Jupiter's gravity is about 2Omega times Earth gravity. The planet has a thin ring and 16 moons. Jupiter rotates in less than ten hours, but its revolution around the Sun takes 11.9 Earth years.
"There is no surface to permit landing. The outer layer of the planet is mostly hydrogen and helium gas. The cloud tops are cold, about -180Cõ¨&orF (-120ÁL&ordC). About 620 mi (1,000 km ) down, the hydrogen changes into liquid form. This hydrogen ocean is 12,500 mi (20,000 km) deep, with a temperature of more than 18,000I&emdash;ü T F (10,000ºC). Lower down, the hydrogen becomes molten like a metal. Scientists believe that inside that layer is a small, rocky core.
"Winds up to 275 mph (450 km/hr) swirl the cloud cover into colored patterns. A large, eye-shaped area named the Great Red Spot is a storm more than three times the size of Earth. This storm has been raging for at least 300 years. Prepare to descend though cloud cover to explore Jupiter."
Brenn thought of wind and cold shields for the ship. Dara remembered the tethers, long cables that could lower and raise things from the ship. Could the robotic arm help?
QUESTIONS
Help Brenn and Dara analyze Jupiter. Use the word groups to the right to label the diagram of Jupiter below. How hot or cold are the two outer layers of Jupiter?
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rocky core layer of liquid metallic (molten) hydrogen layer of liquid hydrogen hydrogen and helium gas |
Writing Assignment: On the back of this sheet, finish this chapter of Brenn and Dara's story. Without a surface to land on, how did they explore Jupiter? What did they find?