Question 1

The protosun ceased to contract when its central temperature became high enough to sustain nuclear reactions.What temperature was this?

Accepted Answer

A)  a million K 
B)  ten million K 
C)  a hundred million K 
D)  700 million K

Question 2

The SMALLEST terrestrial planet is:

Accepted Answer

A)  Neptune. 
B)  Mars. 
C)  Ganymede. 
D)  Mercury.

Question 3

The correct sequence of planets in our solar system from the Sun outward is:

Accepted Answer

A)  Mercury, Earth, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune. 
B)  Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. 
C)  Mercury, Venus, Earth, Mars, Saturn, Uranus, Jupiter, and Neptune. 
D)  Mercury, Venus, Mars, Earth, Jupiter, Saturn, Uranus, and Neptune.

Question 4

Which object is NOT a dwarf planet?

Accepted Answer

A)  Pluto 
B)  Ceres 
C)  Amalthea 
D)  Eris

Question 5

The reason for the vast amount of hydrogen in the interior of Jupiter is probably that:

Accepted Answer

A)  nuclear fission of atoms in Jupiter's interior split all nuclei down to hydrogen nuclei early in its history. 
B)  Jupiter became so hot in its interior that all kinds of atoms and molecules were melted down to the fundamental atom, hydrogen. 
C)  Jupiter formed from the initial gravitational contraction of hydrogen gas. 
D)  the mass of the initial condensation of rocks at Jupiter's orbit was sufficient to attract vast amounts of gas to it.

Question 6

Where in the universe are heavy elements with masses greater than that of helium being produced at this time?

Accepted Answer

A)  in the central cores of stars 
B)  in the surface layers of stars 
C)  at the event horizons of massive black holes 
D)  in the dark clouds of dust and gas

Question 7

A small solar system body CANNOT be a(n):

Accepted Answer

A)  comet. 
B)  asteroid. 
C)  minor planet. 
D)  meteorite.

Question 8

The asteroid belt exists between the orbits of which planets?

Accepted Answer

A)  Jupiter and Saturn 
B)  Venus and Earth 
C)  Mars and Jupiter 
D)  Earth and Mars

Question 9

How long did the formation of the terrestrial planets require in our solar system?

Accepted Answer

A)  a million years 
B)  100 million years 
C)  4.5 billion years 
D)  13.8 billion years

Question 10

What is a protoplanetary disk?

Accepted Answer

A)  a disk of gas and dust, such as those observed around some stars in the Orion nebula 
B)  a disk of debris around a planet of greater mass than Jupiter, material from which rings and moons will form 
C)  a disk of debris orbiting an exoplanet, for example, the planet orbiting the star 51 Pegasi 
D)  a disk of cold debris orbiting far from a star, such as the Oort cloud of our solar system

Question 11

The asteroid Gaspra (see Figure 4-7,Comins,Discovering the Essential Universe,6th ed.)is typical of most asteroids in that it is:

Accepted Answer

A)  potato-shaped with a smooth, metallic surface. 
B)  spherical and densely covered with craters. 
C)  potato-shaped with large and small craters. 
D)  spherical and deformed by thermal activity.

Question 12

Which statement describes the distribution of light and heavy elements in the solar system?

Accepted Answer

A)  The heavy elements are generally within a few astronomical units of the center, while the light elements are generally farther from the center. 
B)  The light elements are generally within a few astronomical units of the center, while the heavy elements are generally farther from the center. 
C)  Both the light and heavy elements are generally within a few astronomical units of the center. 
D)  Both the light and heavy elements are generally farther than a few astronomical units from the center.

Question 13

A theory of the origin of the solar system must take into account all important general properties of the planets.Which statement does NOT describe an important general property of the planets?

Accepted Answer

A)  The planets are grouped by size and composition into three general groups. 
B)  The magnetic fields of the planets are produced by a variety of mechanisms. 
C)  The terrestrial planets all orbit much closer to the Sun than do any of the Jovian planets. 
D)  All the planets orbit the Sun in the same direction and nearly in the same plane.

Question 14

What are the main characteristics of our solar system?

Accepted Answer

A)  four small planets close to the Sun and four large planets far from the Sun 
B)  three small planets close to the Sun and five large planets far from the Sun 
C)  two large planets close to the Sun, three small planets next out, and four large planets farthest from the Sun 
D)  three small planets close to the Sun, four large planets far from the Sun, and one small planet farthest from the Sun

Question 15

The solar system formed about 4.5 billion years ago.What has been the rate of bombardment by space debris in the inner part of the solar system since then?

Accepted Answer

A)  There has been a relatively steady bombardment by both large and small pieces of debris since the formation. 
B)  The rate of bombardment was very heavy just after the solar system's creation, but the rate has decreased steadily since then. 
C)  The rate decreased steadily for about 400 million years after the solar system's creation. Then a very heavy bombardment began and lasted about 300 million years. The rate has been greatly reduced since then. 
D)  The rate has been highly erratic with no clear pattern.

Question 16

Where was all the hydrogen in the universe formed?

Accepted Answer

A)  in nuclear reactions in the cores of stars 
B)  in supernovae (exploding stars) 
C)  in the dark clouds of dust and gas 
D)  in the Big Bang, at the very beginning of the universe

Question 17

What is a plutoid?

Accepted Answer

A)  any object in a 2:3 orbital resonance with Neptune 
B)  any object in the same orbit as Pluto 
C)  any object in an orbit outside that of Pluto 
D)  any object beyond the orbit of Neptune that has enough mass to assume a spherical shape

Question 18

The nebular hypothesis of the formation of the solar system assumes that the material that became the solar system began as a large spherical cloud of gas and dust,rotating slowly.As the solar system formed,most of this material was transformed into a compact,flattened disk,rotating more rapidly.What is the explanation for this change in shape and rate of rotation?

Accepted Answer

A)  conservation of angular momentum 
B)  the influence of nearby stars 
C)  differentiation of materials easily vaporized and not easily vaporized 
D)  alignment with the plane of the Milky Way Galaxy

Question 19

The large gravitational influences of Jupiter and Saturn forced some planetisimals in their neighborhood to move outward away from the Sun.A consequence of these gravitational forces was:

Accepted Answer

A)  that conservation of angular momentum caused the giant planets to spin faster. 
B)  collisions that produced many fragments that became the rings of the outer planets. 
C)  collisions that formed Uranus and Neptune. 
D)  the creation, or at least enlargement, of the Kuiper belt and the Oort cloud.

Question 20

The MOST common elements in the universe are:

Accepted Answer

A)  about equal amounts of all elements up to iron but very little of any heavier elements. 
B)  hydrogen and helium, with small amounts of heavier elements. 
C)  nitrogen and oxygen, with smaller quantities of hydrogen, helium, and heavier elements. 
D)  heavy elements, with smaller quantities of hydrogen and helium.

Exam 4: Formation of the Solar System and Other Planetary Systems