Chapter 6 Quiz Jessica Brandon

Chapter 6 Quiz

1.     What does the solar system look like?

·      Planets are tiny compared to the distances between them.

·      Each world has its own character, but there are many clear patterns.

2.     What features of our solar system provide clues to how it formed?

·      Motions of large bodies:  All in same direction and plane

·      Two major planet types: Terrestrial and jovian

·      —Swarms of small bodies: Asteroids and comets

·      Notable exceptions: Rotation of Uranus, Earth’s large moon, and so forth

3.     What theory best explains the features of our solar system?

·      The nebular theory, which holds that our solar system formed from a cloud of interstellar gas, explains the general features of our solar system.

4.     Where did the solar system come from?

·      Galactic recycling built the elements from which planets formed.

·      We can observe stars forming in other gas clouds.

5.     What caused the orderly patterns of motion in our solar system?

·      The solar nebula spun faster as it contracted because of conservation of angular momentum.

·      Collisions between gas particles then caused the nebula to flatten into a disk.

·      We have observed such disks around newly forming stars.

6.     Why are there two major types of planets?

·      Rock, metals, and ices condensed outside the frost line, but only rock and metals condensed inside the frost line.

·      Small solid particles collected into planetesimals that then accreted into planets.

·      Planets inside the frost line were made of rock and metals.

·      Additional ice particles outside the frost line made planets there more massive, and the gravity of these massive planets drew in H and He gases.

7.     Where did asteroids and comets come from?

·      They are leftover planetesimals, according to the nebular theory.

8.     How do we explain the existence of our Moon and other exceptions to the rules?

·      The bombardment of newly formed planets by planetesimals may explain the exceptions.

·      Material torn from Earth’s crust by a giant impact formed the Moon.

9.     When did the planets form?

·      Radiometric dating indicates that planets formed 4.5 billion years ago.

10. How do we detect planets around other stars?

·      A star’s periodic motion (detected through Doppler shifts) tells us about its planets.

·      Transiting planets periodically reduce a star’s brightness.

·      Direct detection is possible if we can block the star’s bright light.