Question 1

Antarctica is the best hunting ground for meteorites for all of the following reasons EXCEPT
A) the ground is covered with ice in Antarctica.
B) more meteorites fall there than on other locations on Earth.
C) few native rocks are found on the glaciers.
D) meteorites are protected from weathering and contamination there.

Accepted Answer

Meteorites do not fall more frequently in Antarctica than in other locations on Earth. The ice and snow make them easier to spot, and the conditions preserve them well, but the frequency of falls is not higher.

Question 2

The darkest asteroids are
A) M-type.
B) S-type.
C) C-type.
D) Q-type.

Accepted Answer

C-type asteroids are known to be the darkest ones, with low reflectivity due to their high carbon content.

Question 3

The nucleus of the typical comet is approximately __________ in size.
A) 10 km
B) 1,000 km
C) 10 m
D) 1 cm

Accepted Answer

The nucleus of a typical comet is usually around 10 km in size, consisting of ice, dust, and rocky material.

Question 4

Remnants of volcanic activity on the asteroid Vesta indicate that members of the asteroid belt
A) were once part of a single protoplanet that was shattered by collisions.
B) have all undergone significant chemical evolution since formation.
C) occasionally grow large enough to become differentiated and geologically active.
D) were once a part of a young Mars.

Accepted Answer

Some asteroids, like Vesta, are large enough to have undergone differentiation, meaning they have a layered structure similar to planets, indicating past geological activity.

Question 5

The dwarf planet Eris has a moon called Dysomia,which is much smaller in mass than Eris.If Dysomia has an orbital period of 16 days and orbits Eris at a distance of 40,000 km,then what is the mass of Eris?
A) 
B) 
C) 
D)

Accepted Answer

Using Newton's form of Kepler's Third Law, we can find the mass of Eris:
$P^2 = \frac{4\pi^2}{GM}a^3$
Where P is the orbital period, G is the gravitational constant, M is the mass of Eris, and a is the distance between Eris and Dysomia.
Plugging in the given values:
$(16	ext{ days})^2 = \frac{4\pi^2}{G}\frac{(40,000	ext{ km})^3}{M}$
Solving for M, we get:
$M = \frac{4\pi^2}{G}\frac{(40,000	ext{ km})^3}{(16	ext{ days})^2}$
$M = 1.66 	imes 10^{22}$ kg
This is closest to answer choice B.

Question 6

Which of the following does NOT describe comets in the Oort Cloud?
A) Long period
B) Pristine condition
C) Randomly directed orbits
D) Flattened distribution

Accepted Answer

The Oort cloud is believed to have a spherical distribution, so comets in the Oort cloud would not have a flattened distribution.

Question 7

When a comet comes close to the Sun,its volatile ice sublimates and transforms directly from the solid to __________ phase.
A) liquid
B) crystalline
C) gas
D) ionized

Accepted Answer

When the volatile ice on a comet sublimates due to the heat of the Sun, it transforms directly from a solid to a gas phase, without passing through a liquid or crystalline phase. Therefore, the best choice is C, gas.

Question 8

Most asteroids are closest in shape to
A) a potato.
B) an orange.
C) a stick.
D) a baseball.

Accepted Answer

Most asteroids are irregularly shaped and resemble potatoes in shape, rather than the more symmetrical shapes of an orange, stick, or baseball.

Question 9

The mass of all the known asteroids combined would be as much as
A) half the mass of Earth.
B) three times the mass of Earth.
C) the mass of Mars.
D) one-third the mass of the Moon.

Accepted Answer

The combined mass of all known asteroids is estimated to be about one-third the mass of the Moon, which is significantly less than the mass of Earth or Mars.

Question 10

Which group of meteorites represents the conditions in the earliest stages of the formation of the Solar System?
A) Chondrites
B) Achondrites
C) Iron meteorites
D) Stony-iron meteorites

Accepted Answer

Chondrites are the most primitive and oldest type of meteorites, representing the earliest stages of the formation of the Solar System. They are composed of chondrules (spherical grains) that formed from the cooling and solidification of the solar nebula. Achondrites and iron/stony-iron meteorites are formed from differentiated parent bodies, and thus do not represent the earliest stages of Solar System formation.

Question 11

Which of the following is the BRIGHTEST part of a comet?
A) Its nucleus
B) Its coma
C) Its ion tail
D) Its dust tail

Accepted Answer

The coma is the atmosphere of gas and dust that surrounds the nucleus of a comet. It is the brightest part of a comet as it reflects sunlight and emits its own light as well. The nucleus may be larger in size, but it is not as bright as the coma.

Question 12

Which group of asteroids regularly crosses Earth's orbit and thus represents a known collision threat to our planet?
A) The Amors
B) The Atens
C) The Trojans
D) All of the above

Accepted Answer

The Atens are a group of asteroids whose orbits bring them into close proximity with Earth, often crossing Earth's orbit, making them a potential collision threat.

Question 13

Meteorites contain clues to all of the following EXCEPT
A) the age of the Solar System.
B) the temperature in the early solar nebula.
C) changes in the rate of cratering in the early Solar System.
D) the composition of the primitive Solar System.

Accepted Answer

Meteorites do not contain clues about changes in the rate of cratering in the early Solar System.

Question 14

Most asteroids are
A) very large  .
B) large  .
C) medium  .
D) small  .

Accepted Answer

Most asteroids are small, ranging in size from a few feet to several miles in diameter. Only a small fraction of asteroids are considered large or very large.

Question 15

What must an asteroid have in order for us to determine its mass?
A) A rocky composition
B) A moon
C) An orbit that lies between the Earth and Mars
D) Carbonaceous chondrites

Accepted Answer

In order to determine the mass of an asteroid, we need to observe its gravitational effects on other objects in its orbit. One way to do this is to observe a moon or other small object in orbit around the asteroid. By measuring the moon's orbit and applying Newton's laws of gravitation, we can calculate the mass of the asteroid.

Question 16

Comet Halley has a period of
A) 7 years.
B) 16 years.
C) 32 years.
D) 76 years.

Accepted Answer

Comet Halley has a period of 76 years. It was last seen in 1986 and will next be visible from Earth in 2061.

Question 17

Cometary nuclei are most likely
A) solid ice.
B) rocky.
C) porous.
D) uniform.

Accepted Answer

Cometary nuclei are most likely porous, as they are composed of a mixture of ice, dust, and rocky material, which creates a structure with many voids and spaces.

Question 18

The most common type of meteorites are
A) stony meteorites.
B) iron meteorites.
C) stony-iron meteorites.
D) carbonaceous chondrite meteorites.

Accepted Answer

Stony meteorites are the most common type, making up about 90% of all meteorite falls. Iron meteorites are the second most common, making up about 5-6% of meteorite falls. Stony-iron meteorites and carbonaceous chondrite meteorites are much rarer, making up the remaining 4-5% of meteorite falls.

Question 19

Which group of meteoroids is more likely to have compositions indicative of those in the early Solar System?
A) Asteroidal meteoroids
B) Cometary meteoroids
C) Both groups are equally likely
D) Neither group: All meteoroids have undergone significant chemical evolution

Accepted Answer

Cometary meteoroids are more likely to have compositions indicative of those in the early Solar System because comets are thought to be relatively unchanged since the formation of the Solar System. They tend to have a high proportion of volatile compounds that would have been lost from the inner Solar System during its early, high-temperature phase. In contrast, asteroidal meteoroids have undergone more chemical evolution due to heating and differentiation processes.

Question 20

Comet Halley is unique because
A) it was the first comet whose return was predicted.
B) it is a member of the Jovian family but has a retrograde orbit.
C) its period is less than a human lifetime.
D) it was successfully visited by a spacecraft.

Accepted Answer

Comet Halley is unique because it was the first comet whose return was predicted. Its period is around 76 years, so it has been observed by humans for centuries, but it was only when British astronomer Edmond Halley calculated its orbit and predicted its return in 1758 that it became the first comet with a predicted reappearance.

Quiz 12: Dwarf Planets and Small Solar System Bodies

Antarctica is the best hunting ground for meteorites for all of the following reasons EXCEPT

The darkest asteroids are

The nucleus of the typical comet is approximately __________ in size.

Remnants of volcanic activity on the asteroid Vesta indicate that members of the asteroid belt

The dwarf planet Eris has a moon called Dysomia,which is much smaller in mass than Eris.If Dysomia has an orbital period of 16 days and orbits Eris at a distance of 40,000 km,then what is the mass of Eris?

Which of the following does NOT describe comets in the Oort Cloud?

When a comet comes close to the Sun,its volatile ice sublimates and transforms directly from the solid to __________ phase.

Most asteroids are closest in shape to

The mass of all the known asteroids combined would be as much as

Which group of meteorites represents the conditions in the earliest stages of the formation of the Solar System?

Which of the following is the BRIGHTEST part of a comet?

Which group of asteroids regularly crosses Earth's orbit and thus represents a known collision threat to our planet?

Meteorites contain clues to all of the following EXCEPT

Most asteroids are

What must an asteroid have in order for us to determine its mass?

Comet Halley has a period of

Cometary nuclei are most likely

The most common type of meteorites are

Which group of meteoroids is more likely to have compositions indicative of those in the early Solar System?

Comet Halley is unique because