Question 1

The nuclei of a comet is mostly:

Accepted Answer

A) solid ice 
B) solid rock 
C) liquid water 
D) a porous mix of ice and dust 
E) frozen carbon dioxide 
A) solid ice 
B) solid rock 
C) liquid water 
D) a porous mix of ice and dust 
E) frozen carbon dioxide

Question 2

Most comets originate:

Accepted Answer

A) near Earth and Venus in the early Solar System 
B) far from the planets,many thousands of AU from the Sun 
C) from the region between the orbits of Jupiter and Neptune 
D) between the Sun and Mercury 
E) between the orbits of Mars and Jupiter 
A) near Earth and Venus in the early Solar System 
B) far from the planets,many thousands of AU from the Sun 
C) from the region between the orbits of Jupiter and Neptune 
D) between the Sun and Mercury 
E) between the orbits of Mars and Jupiter

Question 3

Consider three comets that have orbital periods of 10,100,and 1,000 years.Where would each of these comets likely originate,in the Oort Cloud or the Kuiper Belt? If you wanted to study material that was the best example of pristine Solar System material,which would you study?

Accepted Answer

For all objects,including comets,that or

Question 4

The most straightforward way to determine the mass of an asteroid is if it has:

Accepted Answer

A) a rocky composition 
B) a moon 
C) an orbit that lies between the Earth and Mars 
D) carbonaceous chondrites 
E) a magnetic field 
A) a rocky composition 
B) a moon 
C) an orbit that lies between the Earth and Mars 
D) carbonaceous chondrites 
E) a magnetic field

Question 5

Until spacecraft flew by asteroids,scientists did not have a good idea of what they looked like.Which of the following missions was the first to fly by an asteroid?

Accepted Answer

A) NEAR Shoemaker 
B) Rosetta 
C) Galileo 
D) Dawn 
E) Stardust 
A) NEAR Shoemaker 
B) Rosetta 
C) Galileo 
D) Dawn 
E) Stardust

Question 6

Pluto is classified as a dwarf planet because:

Accepted Answer

A) it has not cleared out other bodies from its orbit 
B) it is over 1,000 times smaller than the Earth's moon 
C) it has no moons of its own 
D) it has a unique chemical composition that is very different from other planets 
E) it orbits just outside the Solar System 
A) it has not cleared out other bodies from its orbit 
B) it is over 1,000 times smaller than the Earth's moon 
C) it has no moons of its own 
D) it has a unique chemical composition that is very different from other planets 
E) it orbits just outside the Solar System

Question 7

With a semimajor axis of 18 AU,Comet Halley has a period of:

Accepted Answer

A) 7 years 
B) 16 years 
C) 32 years 
D) 67 years 
E) 76 years 
A) 7 years 
B) 16 years 
C) 32 years 
D) 67 years 
E) 76 years

Question 8

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

Accepted Answer

A) liquid 
B) crystalline 
C) energized 
D) gas 
E) ionized 
A) liquid 
B) crystalline 
C) energized 
D) gas 
E) ionized

Question 9

Approximately how often does a spectacularly active,visible comet appear?

Accepted Answer

A) once a year 
B) once every 5 years 
C) once every 10 years 
D) once every 50 years 
E) once every 1,000 years 
A) once a year 
B) once every 5 years 
C) once every 10 years 
D) once every 50 years 
E) once every 1,000 years

Question 10

All short-period comets have periods less than or equal to 20 years.

Accepted Answer

A) True 
 B)False

Question 11

Describe two modern-day (within the past 150 years)events when comets or asteroids collided with a planet.Cite the planet,and describe the major consequences of the collision.

Accepted Answer

Shoemaker-Levy 9 crashed into Jupiter's

Question 12

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

Accepted Answer

A) long period 
B) pristine condition 
C) cold temperatures 
D) randomly directed orbits 
E) flattened distribution 
A) long period 
B) pristine condition 
C) cold temperatures 
D) randomly directed orbits 
E) flattened distribution

Question 13

In its 1986 trip around the Sun,it was estimated that Comet Halley lost approximately 100 billion kg of material.The total mass of the nucleus was estimated to be 3 × 1014 kg.Assuming the mass loss rate is constant with each passage,and assuming the nucleus remains intact until there is nothing left,how many more times will we see Comet Halley? Explain why your answer is an upper limit.

Accepted Answer

The number of trips equals the total mas

Question 14

While most meteorites have ages around 4.5 billion years,a small subset have ages around 1.3 billion years.What caused the substantial difference in age between these two populations of meteorites?

Accepted Answer

A) These meteorites just happened to form later than most meteorites. 
B) Not all meteorites hit the Earth in the early Solar System.We should expect to find younger meteorites as more meteors pass through the atmosphere. 
C) The younger meteorites were created when a protoplanet collided with Earth,creating the Moon.The leftover fragments became meteorites. 
D) These meteorites were thrown into space after an impact with Mars and afterward some happened to collide with Earth. 
E) The younger ones are the result of comets repeatedly passing close to the Sun,melting their surfaces and making them appear younger. 
A) These meteorites just happened to form later than most meteorites. 
B) Not all meteorites hit the Earth in the early Solar System.We should expect to find younger meteorites as more meteors pass through the atmosphere. 
C) The younger meteorites were created when a protoplanet collided with Earth,creating the Moon.The leftover fragments became meteorites. 
D) These meteorites were thrown into space after an impact with Mars and afterward some happened to collide with Earth. 
E) The younger ones are the result of comets repeatedly passing close to the Sun,melting their surfaces and making them appear younger.

Question 15

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

Accepted Answer

A) 10 km 
B) 1,000 km 
C) 100 m 
D) 10 m 
E) 1 cm 
A) 10 km 
B) 1,000 km 
C) 100 m 
D) 10 m 
E) 1 cm

Question 16

The mass of Pluto is approximately 100 times less than that of Earth.

Accepted Answer

A) True 
 B)False

Question 17

The minimum size of a meteoroid that is capable of surviving its passage through the Earth's atmosphere and hitting the ground is about as big as:

Accepted Answer

A) a car 
B) a house 
C) a basketball 
D) a grain of sand 
E) your fist 
A) a car 
B) a house 
C) a basketball 
D) a grain of sand 
E) your fist

Question 18

Currently the surface of the dwarf planet Eris is covered with _________,which makes it have the highest albedo of any object in the Solar System.

Accepted Answer

A) methane ice 
B) water ice 
C) nitrogen ice 
D) sulfur dioxide ice 
E) carbon dioxide ice 
A) methane ice 
B) water ice 
C) nitrogen ice 
D) sulfur dioxide ice 
E) carbon dioxide ice

Question 19

Most asteroids are:

Accepted Answer

A) very large ( >100 km) B) large (30-100 km) C) medium (10-30 km) D) small (1-10 km) E) very small (< 1 km) A) very large ( >100 km) B) large (30-100 km) C) medium (10-30 km) D) small (1-10 km) E) very small (< 1 km)

Question 20

The most common type of meteorites found are iron meteorites.

Accepted Answer

A) True 
 B)False

Exam 12: Dwarf Planets and Small Solar System Bodies

The nuclei of a comet is mostly:

Most comets originate:

Consider three comets that have orbital periods of 10,100,and 1,000 years.Where would each of these comets likely originate,in the Oort Cloud or the Kuiper Belt? If you wanted to study material that was the best example of pristine Solar System material,which would you study?

The most straightforward way to determine the mass of an asteroid is if it has:

Until spacecraft flew by asteroids,scientists did not have a good idea of what they looked like.Which of the following missions was the first to fly by an asteroid?

Pluto is classified as a dwarf planet because:

With a semimajor axis of 18 AU,Comet Halley has a period of:

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

Approximately how often does a spectacularly active,visible comet appear?

All short-period comets have periods less than or equal to 20 years.

Describe two modern-day (within the past 150 years)events when comets or asteroids collided with a planet.Cite the planet,and describe the major consequences of the collision.

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

While most meteorites have ages around 4.5 billion years,a small subset have ages around 1.3 billion years.What caused the substantial difference in age between these two populations of meteorites?

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

The mass of Pluto is approximately 100 times less than that of Earth.

The minimum size of a meteoroid that is capable of surviving its passage through the Earth's atmosphere and hitting the ground is about as big as:

Currently the surface of the dwarf planet Eris is covered with _________,which makes it have the highest albedo of any object in the Solar System.

Most asteroids are:

The most common type of meteorites found are iron meteorites.

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornments Moons and Rings

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters