Question 1

Two comets approach the Sun with the same perihelion distance.Comet A's orbit has a higher eccentricity and is more inclined relative to the ecliptic than comet B's orbit.Which comet is more likely to come from the Oort Cloud?

Accepted Answer

Comet A.

Question 2

A comet is best described as a:

Accepted Answer

A)   ball of gas.
B)   ball of ice.
C)   dirty snowball.
D)   carbonaceous rock. C

Question 3

Giant planets attain their atmospheres through:

Accepted Answer

A)   collisions of gaseous protoplanets.
B)   migration.
C)   binary accretion.
D)   processes that are not yet well understood. D

Question 4

What is the key difference between the core accretion and hydrodynamic instability models for gas giant formation?

Accepted Answer

The answer of What is the key difference between the...

Question 5

Two planets,A and B,have identical compositions.Planet A has an orbital radius of 0.5 AU and a mass equal to 0.5 Earth masses.Planet B has an orbital radius of 1 AU and a mass equal to 1 Earth mass.Which planet is denser? Why?

Accepted Answer

The answer of Two planets,A and B,have identical compositions.Planet A...

Question 6

A Solar System body with a dozen moons,a mass of 15 Earth masses,and strong magnetic fields is most likely a(n):

Accepted Answer

A)   dwarf planet.
B)   terrestrial planet.
C)   gas giant.
D)   ice giant.

Question 7

Pluto is closest in mass to:

Accepted Answer

A)   Ceres.
B)   Mercury.
C)   Earth's Moon.
D)   Eris.

Question 8

Hot Jupiters provide evidence for:

Accepted Answer

A)   the greenhouse effect.
B)   super-Earths.
C)   the condensation theory.
D)   planetary migration.

Question 9

A star-exoplanet system is oriented on the sky as shown in the figure below,which shows several snapshots of the planet's orbit.How could astronomers measure the density of this planet?

Accepted Answer

The answer of A star-exoplanet system is oriented on the...

Question 10

A meteor shower occurs when:

Accepted Answer

A)   an asteroid breaks up near Earth.
B)   Earth passes through the asteroid belt.
C)   Earth passes through a comet's orbit.
D)   a comet breaks up near Earth.

Question 11

An interstellar cloud of gas and dust with a radius of 10⁵ AU rotates slowly,with its outer edge traveling at 10⁻³ km/s.How fast is the outer edge of the cloud rotating after it contracts to 100 AU?

Accepted Answer

A)   10-1 km/s
B)   1 km/s
C)   100 km/s
D)   103 km/s

Question 12

The orbits of the planets in our Solar System:

Accepted Answer

A)   imply that the planets formed elsewhere and were captured by the Sun's gravity.
B)   all proceed in the same direction.
C)   have a wide range of inclinations.
D)   have semimajor axes that follow a regular, repeating pattern.

Question 13

Compared to our Solar System,the majority of exoplanets have orbits with:

Accepted Answer

A)   higher eccentricity.
B)   higher inclinations.
C)   smaller semimajor axes.
D)   all of the above.

Question 14

Compare the following properties between Mars and Jupiter: mass,orbital radius,rotation rate,and density.

Accepted Answer

The answer of Compare the following properties between Mars and...

Question 15

A planet orbiting a star with a mass one-quarter that of the Sun has an orbital radius of 1/25 AU.If Earth's orbital velocity is 30 km/s,what is the orbital velocity of this planet?

Accepted Answer

A)   15 km/s
B)   30 km/s
C)   60 km/s
D)   75 km/s

Question 16

Why do the compositions of planets in our Solar System depend on distance from the Sun?

Accepted Answer

The answer of Why do the compositions of planets in...

Question 17

The figure below shows the orbits of planets within our Solar System (not to scale),with three of the orbits labeled by letters A,B,and C.Which type of planet is most likely to follow each of these orbits?

Accepted Answer

The answer of The figure below shows the orbits of...

Question 18

Suppose Jupiter's orbit suddenly became highly eccentric.How would this affect the Solar System?

Accepted Answer

The answer of Suppose Jupiter's orbit suddenly became highly eccentric.How...

Question 19

An icy,rocky body on a highly elliptical orbit through our Solar System is most likely a:

Accepted Answer

A)   Kuiper Belt object.
B)   asteroid.
C)   comet.
D)   dwarf planet.

Question 20

Among the terrestrial planets,which of the following properties decreases with distance from the Sun?

Accepted Answer

A)   mass
B)   uncompressed density
C)   radius
D)   rotation rate

Exam 5: The Architecture and Birth of Planetary Systems