Chapter 15

Distinguish between a meteoroid, a meteor, and a meteorite.

Explain why the meteors in a given shower appear to be diverging from a fixed point in the sky.

Why are carbonaceous chondrites especially important for the study of the early solar system?

What does the cosmic ray exposure age tell us about the history of a meteorite?

Ceres, the first asteroid to be discovered, lies between Mars and Jupiter. Why was Ceres unknown to ancient astronomers?

What is the relationship between asteroids and meteorites?

Describe what happens to the nucleus of a comet as it moves from 10 AU from the Sun to 0.5 AU from the Sun.

Why do the dust tail and the plasma tail of a comet point away from the Sun?

What evidence is there that the Sun is surrounded by a vast cloud of comets known as the Oort cloud?

What causes Oort cloud comets to enter the inner solar system and become visible as new comets?

What is the eventual fate of most short-period and long-period comets?

What is the relationship between comets and meteor showers?

What evidence do we have that comets are permanent solar system members rather than interlopers from other parts of the galaxy?

Suppose the Earth were struck by an asteroid \(10 \mathrm{km}\) in diameter. Describe the local and global consequences of the impact.