Question 1

As the solar nebula contracts it:
A) flattens out into the ecliptic plane around the Sun's poles.
B) spins faster due to conservation of angular momentum.
C) cools due to condensation.
D) loses angular momentum.
E) reverses it direction of rotation.

Accepted Answer

As the solar nebula contracts, it spins faster due to the conservation of angular momentum, similar to how a figure skater spins faster when pulling in their arms.

Question 2

A successful theory of the formation of the solar system must explain:
A) that all planets rotate in a prograde sense.
B) that all planets have elliptical orbits with high eccentricities.
C) the existence of the asteroid belt between Jupiter and Neptune.
D) that the inner planets have more hydrogen and helium in their atmospheres than do the outer planets.
E) all observed properties of the solar system.

Accepted Answer

A successful theory of the formation of the solar system must be able to explain all observed properties of the solar system, including but not limited to the prograde rotation of all planets, the elliptical orbits with different eccentricities, the existence of the asteroid belt, and the differences in atmospheric composition between inner and outer planets.

Question 3

Planetary orbits:
A) are evenly spaced throughout the solar system.
B) are highly inclined to the ecliptic.
C) are almost circular, with low eccentricities.
D) have the Sun at their exact center.
E) are spaced more closely together as they get further from the Sun.

Accepted Answer

Planetary orbits are almost circular with low eccentricities, meaning they are relatively uniform in shape and size. They are not evenly spaced throughout the solar system, nor are they highly inclined to the ecliptic or spaced more closely together as they get further from the Sun. Additionally, the Sun is not at the exact center of each planet's orbit, but rather located at one of the foci of the ellipse that defines the orbit.

Question 4

Dust is an important part of the nebular theory of solar system formation because dust is needed to explain:
A) how the inner planets came to be rocky bodies.
B) how the outer planets came to be gaseous bodies.
C) how the initial cloud cooled enough to collapse.
D) how the initial cloud heated as it contracted.
E) why the icy bodies are located so far from the Sun.

Accepted Answer

The answer of Dust is an important part of the...

Question 5

As a rotating gas cloud contracts,it spins:
A) faster due to an increase in angular momentum.
B) slower due to a decrease in angular momentum.
C) at a constant rate.
D) faster due to conservation of angular momentum.
E) slower due to conservation of angular momentum.

Accepted Answer

As the gas cloud contracts, its angular momentum is conserved, but its moment of inertia decreases due to the shrinking size. Therefore, the rotation rate must increase to conserve angular momentum, resulting in faster spinning.

Question 6

The meteorites that strike Earth are:
A) pieces of comets that fall to Earth.
B) mostly made of iron.
C) the oldest rocks known.
D) the remains of the planet between Mars and Jupiter.
E) material from outside our solar system.

Accepted Answer

The answer of The meteorites that strike Earth are:
A) pieces...

Question 7

Which of these is NOT a characteristic of the solar nebula theory?
A) The ecliptic is the equator for the Sun.
B) All the planets should follow the ecliptic plane.
C) All the planets should orbit the Sun counterclockwise.
D) Larger planets should form closer to their star, where there is more debris.
E) Planets should rotate counterclockwise as well.

Accepted Answer

The solar nebula theory proposes that planets form from the debris disk around a newly formed star. However, it does not necessarily dictate that larger planets should form closer to their star. There are different factors that influence where and how planets form, such as the composition of the debris and the gravitational interactions between different bodies.

Question 8

What might have made the original solar nebula begin to contract?
A) the Big Bang
B) the formation of our arm of the Milky Way
C) the shock wave from a nearby exploding star
D) interstellar magnetism generated by pulsars
E) the large amount of angular momentum in the nebula

Accepted Answer

The shock wave from a nearby exploding star (supernova) could have provided the necessary external pressure or trigger to initiate the contraction of the original solar nebula, leading to the formation of the Solar System. This process is supported by evidence of short-lived radioactive isotopes found in meteorites, which are thought to be remnants of the early Solar System and could have been produced by nearby supernovae.

Question 9

In the conventional scenario,during phase of planet formation caused the jovian planets to form?
A) core-accretion
B) fragmentation
C) differentiation
D) collision
E) condensation

Accepted Answer

The core-accretion model is the conventional scenario of how jovian planets form. It states that gas giants form from the accumulation of planetesimals (small, solid bodies) in the protoplanetary disk. These planetesimals collide and stick together, forming larger objects called protoplanets. As these protoplanets grow, they gravitationally attract gas from the disk and continue to grow into gas giants. This process is called core-accretion.

Question 10

What was the primary role of dust in the formation of the solar system?
A) Dust formed the rings around Uranus, Neptune, and Jupiter.
B) Dust veiled the process by which our solar system formed.
C) Dust acted as condensation nuclei; platforms to which other particles could attach and form larger particles of matter.
D) The Sun formed from a vast spinning cloud consisting only of dust.
E) Dust provided the radioactive elements that initially heated the Sun.

Accepted Answer

Dust acted as condensation nuclei; platforms to which other particles could attach and form larger particles of matter. Dust played a critical role in the formation of the solar system by providing a surface for other particles to adhere to and eventually accumulate into planets and other objects in the solar system.

Question 11

What factor caused different planets to form out of different types of material?
A) The angular momentum of the forming planet; faster rotating planets lost the lightest elements.
B) The quantity of dust particles in the solar nebula; more dust caused some planets to contain heavier elements.
C) The variation in temperature throughout the solar nebula; the higher the temperature, the lower the percentage of light elements in the forming planet.
D) The angular momentum of the solar nebula pushed the heavy elements towards the outer regions of the nebula.
E) The innate variation of chemical composition of the original nebula; the outer parts of the nebula contained a greater abundance of heavy elements.

Accepted Answer

The variation in temperature throughout the solar nebula played a crucial role in determining the types of materials that could condense and form into planets. Closer to the Sun, where temperatures were higher, only metals and silicates could condense, leading to the formation of terrestrial planets. Further out, where it was cooler, gases and ices could also condense, contributing to the formation of gas giants and ice giants.

Question 12

An alternative to the core-accretion theory that explains the formation of the jovian planets is the:
A) differentiation theory.
B) collision theory.
C) gravitational instability theory.
D) Big Bang theory.
E) nebular contraction theory.

Accepted Answer

The gravitational instability theory proposes that the jovian planets formed through the direct collapse of a massive, dense cloud of gas and dust within the protoplanetary disk, rather than through the gradual accumulation of solid particles onto a rocky core as in the core-accretion theory. This theory can account for the rapid formation of the jovian planets and their large masses, as well as their location far from the Sun.

Question 13

What happens when a solar nebula contracts?
A) It flattens out.
B) It spins faster.
C) It heats up.
D) All of the above.
E) None of the above.

Accepted Answer

When a solar nebula contracts, it conserves its angular momentum and, as a result, spins faster and flattens out. Due to the conservation of energy, the potential energy of the nebula converts into kinetic energy, which results in a heating up of the nebula. Therefore, all of the above options are correct.

Question 14

The jovian planets:
A) all lie less than 5 AU from the Sun.
B) all have rings around their equators.
C) all spin slower than the Earth.
D) have satellite systems with less than 4 moons.
E) are all much more dense than any of the terrestrials planets.

Accepted Answer

Only the jovian planets have rings around their equators.

Question 15

Conservation of angular momentum means that a spinning body tends to:
A) fly apart.
B) slow down.
C) wobble into an eccentric orbit.
D) gravitationally collapse.
E) keep spinning.

Accepted Answer

Conservation of angular momentum states that the total angular momentum of a system remains constant unless acted upon by an external torque. This means that a spinning body will tend to keep spinning because there is no external force acting on it to slow it down or stop it.

Question 16

What is the process of accretion?
A) the separation of materials in a protoplanet by density, with dense material in core
B) growth of an object by the accumulation of matter
C) the breakup of large objects by violent collisions with other similar-sized objects
D) the period of time during which the Sun swept away all the excess material in the solar nebula
E) the process by which the solar nebula became heated during its collapse

Accepted Answer

Accretion is the process of an object increasing in size by the accumulation of matter, such as the growth of planets from smaller planetesimals in the solar system.

Question 17

One possible way that future scientists may determine whether the core-accretion model or the gravitational instability theory better explains the formation of the jovian planet is:
A) measuring the mass of the rocky material in the jovian planets' cores.
B) measuring the metallic hydrogen layer in the jovian planets.
C) observing the changes in the rings around the jovian planets.
D) observing the changes in the magnetic fields of the jovian planets.

Accepted Answer

Measuring the mass of the rocky material in the jovian planets' cores would help determine whether the core-accretion model or gravitational instability theory is more accurate, as the core-accretion model suggests that such planets formed from the accumulation of solid materials that eventually formed a rocky core, while the gravitational instability theory predicts that the planets formed as gas and dust collapsed under their own gravity without the need for a rocky core. By measuring the mass of the rocky core, scientists can determine which theory is more accurate. Measuring the metallic hydrogen layer or observing the changes in the rings or magnetic fields of the jovian planets does not directly relate to the formation theories. The core-accretion model predicts that a solid core of rocky material forms first, which then attracts gas from the surrounding disk to form a giant planet. The gravitational instability theory suggests that a clump of gas in the disk collapses under its own gravity to form a giant planet. By measuring the mass of the rocky material in the jovian planets' cores, scientists can determine whether the amount of core material is consistent with the core-accretion model or the gravitational instability theory.

Question 18

In light of modern solar system theory,why do the orbits of the planets all lie in the same plane?
A) The Sun's gravity forced them into these orbits.
B) The angular momentum of the solar system was kept to a minimum this way.
C) The early solar nebula flattened into a disk.
D) Comets would have wiped out any not in this protected plane.
E) This happened purely by chance.

Accepted Answer

The most widely accepted explanation for why the orbits of the planets all lie in the same plane is that the early solar nebula flattened into a disk. As the nebula coalesced into the solar system, conservation of angular momentum caused the material to rotate around the protosun in a common plane. This resulted in the formation of a flat, swirling disk of gas and dust that eventually gave rise to the planets.

Question 19

The moons of the jovian planets formed by which two processes?
A) accretion and collisions
B) capture and collisions
C) collisions and differentiation
D) accretion and capture
E) differentiation and capture

Accepted Answer

The most widely accepted theory for the formation of Jovian moons is that they formed through a combination of accretion (the process by which small particles stick together to form larger particles) and capture (when a moon is captured by the planet's gravity after forming elsewhere in the solar system). Collisions and differentiation may have played a role in shaping the moons after their formation, but they were not the primary processes that formed them.

Question 20

What is true about solar system densities?
A) The denser planets lie closer to the Sun.
B) In differentiated bodies, the denser materials lie near their surfaces.
C) The asteroids all have about the same density.
D) Saturn has the same density as water.
E) Planetary density increases with increasing distance from the Sun.

Accepted Answer

The answer of What is true about solar system densities?
A)...

Quiz 6: The Solar System: Comparative Planetology and Formation Models

As the solar nebula contracts it:

A successful theory of the formation of the solar system must explain:

Planetary orbits:

Dust is an important part of the nebular theory of solar system formation because dust is needed to explain:

As a rotating gas cloud contracts,it spins:

The meteorites that strike Earth are:

Which of these is NOT a characteristic of the solar nebula theory?

What might have made the original solar nebula begin to contract?

In the conventional scenario,during phase of planet formation caused the jovian planets to form?

What was the primary role of dust in the formation of the solar system?

What factor caused different planets to form out of different types of material?

An alternative to the core-accretion theory that explains the formation of the jovian planets is the:

What happens when a solar nebula contracts?

The jovian planets:

Conservation of angular momentum means that a spinning body tends to:

What is the process of accretion?

One possible way that future scientists may determine whether the core-accretion model or the gravitational instability theory better explains the formation of the jovian planet is:

In light of modern solar system theory,why do the orbits of the planets all lie in the same plane?

The moons of the jovian planets formed by which two processes?

What is true about solar system densities?