ASTR1010 Unit 3 Practice test

TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false.

1) One bar of atmosphere is roughly equal to the Earth's atmospheric pressure at sea level.

2) A planet with an albedo of 10 percent absorbs 10 percent of the sunlight that strikes it and

reflects the other 90 percent.

3) Sunsets are red because sunlight must pass through more atmosphere then, and the

atmosphere scatters even more light at bluer wavelengths, transmitting mostly red light.

4) Without greenhouse gases, Earth's surface would be frozen over.

5) If Jupiter were 10 times more massive, it would generate nuclear fusion in its core and be a

star instead of a planet.

6) Jupiter's Great Red Spot is a low-pressure storm like a hurricane on Earth.

7) Some of the moons of the Jovian planets have significant atmospheres.

8) All meteorites collected on Earth come from asteroids or comets.

9) Oort-cloud comets are so far from the Sun that the gravity of neighboring stars can alter their orbits.

10) Pluto's gravity affects the orbit of Uranus, and this fact was used to discover Pluto.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

11) Which of the following correctly describes the meaning of albedo?

A) The lower the albedo, the more light the surface reflects, and the less it absorbs.

B) The higher the albedo, the more light the atmosphere absorbs.

C) The higher the albedo, the more light the surface absorbs.

D) The higher the albedo, the more light the surface emits.

E) The higher the albedo, the more light the surface reflects, and the less it absorbs.

12) A planet that is three times farther from the Sun than another planet receives how much sunlight per square meter compared to the closer planet?

A) three times less

B) three times more

C) nine times less

D) six times more

E) six times less

13) What are greenhouse gases?

A) gases that absorb visible light

B) gases that transmit infrared light

C) gases that absorb infrared light

D) gases that absorb ultraviolet light

E) gases that transmit visible light

14) Which of the following gases absorbs ultraviolet light best?

A) nitrogen

B) oxygen

C) carbon dioxide

D) ozone

E) hydrogen

15) Why does Mars have more extreme seasons than Earth?

A) because it has a larger axis tilt

B) because it has a more eccentric orbit

C) because it is farther from the Sun

D) because it has more carbon dioxide in its atmosphere

E) all of the above

16) What is differential rotation?

A) when storms in the northern hemisphere rotate counterclockwise while storms in the

southern hemisphere rotate clockwise

B) when a body rotates faster or slower at its equator than it does at its poles

C) when a planet's rotation changes through evolution

D) when a planet's rotation changes due to a catastrophic event

E) when the core of a planet rotates at a different rate than its atmosphere

17) How much energy does Jupiter emit compared with how much it receives from the Sun?

A) It emits 1 percent as much.

B) It emits 10 times as much.

C) It emits half as much.

D) It emits twice as much.

E) It emits 10 percent as much.

18) The belts and zones of Jupiter are

A) cyclonic and anticyclonic storms.

B) names for different cloud layers on Jupiter.

C) alternating regions of charged particles in Jupiter's magnetic field.

D) alternating bands of rising and falling air at different latitudes.

19) Why are there no impact craters on the surface of Io?

A) It is too small to have been bombarded by planetesimals in the early solar system.

B) Io's thick atmosphere obscures the view of the craters.

C) Jupiter's strong gravity attracted the planetesimals more strongly than Io and thus none

landed on its surface.

D) Any craters that existed have been eroded through the strong winds on Io's surface.

E) Io did have impact craters but they have all been buried in lava flows.

20) Most of the moons of the jovian planets are

A) between 300 and 1,500 km in diameter.

B) between 1,500 and 5,000 km in diameter.

C) smaller than 300 km across.

D) more than 5,000 km in diameter.

21) A rocky leftover planetesimal orbiting the Sun is

A) a meteorite.

B) an asteroid.

C) a meteor.

D) a comet.

E) possibly any of the above.

22) Where are the Trojan asteroids located?

A) on orbits that cross Mars's orbit

B) on orbits that cross Earth's orbit

C) surrounding Jupiter

D) along Jupiter's orbit, 60e ahead of and behind Jupiter

E) in the center of the asteroid belt

23) The large gaps in the asteroid belt (often called Kirkwood gaps) are caused by

A) orbital resonances with Jupiter.

B) tidal forces from Jupiter.

C) the competing gravitational tugs of Mars and Jupiter.

D) tidal forces from the Sun.

E) large asteroids that clear certain regions of the asteroid belt.

24) Comets with extremely elliptical orbits, like comets Hyakutake and Hale-Bopp,

A) come from the Kuiper belt.

B) are captured by Jupiter.

C) come from the Oort cloud.

D) are Trojan comets.

E) come from the asteroid belt.

25) When was Pluto discovered?

A) about 2000 years ago

B) about 70 years ago

C) about 20 years ago

D) about 200 years ago

E) in ancient history

1) Answer: TRUE

2) Answer: FALSE

3) Answer: TRUE

4) Answer: TRUE

5) Answer: FALSE

6) Answer: FALSE

7) Answer: TRUE

8) Answer: FALSE

9) Answer: TRUE

10) Answer: FALSE

11) Answer: E

12) Answer: C

13) Answer: C

14) Answer: D

15) Answer: B

16) Answer: B

17) Answer: D

18) Answer: D

19) Answer: E

20) Answer: C

21) Answer: B

22) Answer: D

23) Answer: A

24) Answer: C

25) Answer: B