Earth and Space Science / Unit 9: The Solar System
9.4 Moons, Asteroids and Comets
Notes
- Moons: Earth's Moon likely formed from debris after a Mars-sized body hit early Earth (giant impact). It has craters, dark maria (basalt plains), no air.
- Asteroids: rocky bodies mostly in the asteroid belt between Mars and Jupiter.
- Comets: icy bodies from the Kuiper Belt and Oort Cloud; they grow a glowing coma and tail near the Sun, and the tail points away from the Sun.
- A meteoroid is a small piece of space rock; a meteor is its streak of light in the atmosphere; a meteorite reaches the ground.
Practice
A comet's tail points:
Solar wind and radiation push material away.
The asteroid belt lies between:
Between the terrestrial planets and gas giants.
A rock from space that lands on Earth's surface is called a:
Meteorite refers to a piece that survived landing.
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