# Chap 1

## Unlock all answers in this set

question
What is the meaning of the word cosmos? A) the origin of Earth and life upon it B) the light from a distant astronomical object C) the Milky Way D) the sum total of all matter and energy, that is, everything within and between all galaxies E) the dark sky
The sum total of all matter and energy, that is, everything within and between all galaxies.
question
Put your "address" in the correct order. A) you, Earth, solar system, Local Group, Local Supercluster, Milky Way B) you, Earth, solar system, Milky Way, Local Supercluster, Local Group C) you, Earth, solar system, Local Group, Milky Way, Local Supercluster D) you, Earth, Local Group, Local Supercluster, solar system, Milky Way E) you, Earth, solar system, Milky Way, Local Group, Local Supercluster
You, Earth, solar system, Milky Way, Local Group, Local Supercluster.
question
About where is our solar system located within the Milky Way Galaxy? A) at the center of the galaxy B) about 10 percent of the way from the center of the galaxy to the outskirts of the galactic disk C) about two-thirds of the way from the center of the galaxy to the outskirts of the galactic disk D) near the far outskirts of the galactic disk E) in the halo of the galaxy above the galactic disk
About two-thirds of the way from the centre of the galaxy to the outskirts of the galactic disk.
question
Roughly how many stars are in the Milky Way Galaxy? A) 1 billion B) 100 billion C) 10 billion D) 100 million E) 100 trillion
100 billion
question
Modern telescopes are capable of seeing bright galaxies up to about: A) 1 million light-years away. B) 10 million light-years away. C) 1 billion light-years away. D) 10 billion light-years away. E) 1 trillion light-years away.
10 billion light-years away.
question
Suppose we imagine the Sun to be about the size of a grapefruit. How big an area would the orbits of the eight planets of the solar system cover? A) the size of a typical dorm room B) the size of a typical campus building C) the size of a typical campus D) the size of a small city E) the size of a western state (e.g., Colorado)
The size of a typical campus.
question
What do we mean when we say that the universe is expanding? A) Average distances are increasing between star systems within galaxies. B) Everything in the universe is gradually growing in size. C) Average distances are increasing between galaxies. D) The statement is not meant to be literal; rather, it means that our knowledge of the universe is growing. E) Individual galaxies are gradually growing in size.
Average distances are increasing between galaxies.
question
The age of the universe is A) between 10 million and 16 million years. B) between 100 million and 160 million years. C) between 1 billion and 1.6 billion years. D) between 10 billion and 16 billion years. E) between 100 billion and 160 billion years.
Between 10 billion and 16 billion years.
question
How are galaxies important to our existence? A) Without galaxies, there could not have been a Big Bang. B) Without galaxies, the universe could not be expanding. C) Galaxies prevent planets from leaving their orbits around stars; e.g., our galaxy prevents Earth from leaving its orbit of the Sun. D) Galaxies recycle heavy elements produced in stars into future generations of stars. E) Galaxies provide the gravity that prevents us from falling off Earth.
Galaxies recycle heavy elements produced in stars into future generations of stars.
question
Earth is made mostly of metals and rocks. Where did this material come from? A) It was produced in the Big Bang. B) It was created by chemical reactions in interstellar space. C) It was produced by nuclear fusion in stars. D) It was made by our Sun. E) It was made by nuclear fission of uranium and other radioactive materials.
It was produced by nuclear fusion in stars.
question
What is nuclear fusion? A) an explosion caused by putting together two volatile chemicals B) the process of splitting nuclei to produce energy C) the process of turning matter into pure energy D) the process of combining lightweight nuclei to make heavier nuclei E) a process that only occurs in bombs
The process of combining lightweight nuclei to make heavier nuclei.
question
Why did Carl Sagan say that we are star stuff? A) The composition of most stars (mostly hydrogen and helium) is about the same as the composition of our bodies. B) Cosmic rays reaching Earth from distant astronomical sources may be one source of mutations that help evolution along. C) Nearly every atom from which we are made once (before the solar system formed) was inside of a star. D) Nearly every atom from which we are made was once inside our star, the Sun. E) Sagan thought that all of us have the potential to be movie (or TV) stars like he was.
Nearly every atom from which we are made once (before the solar system formed) was inside of a star.
question
One light-hour is the distance that light travels in an hour. How far is this, in kilometers? (Recall that the speed of light is 300,000 km/s.) A) 300,000 km B) 18 million km C) 100 million km D) 1.08 billion km E) 9.46 trillion km
1.08 billion km.
question
Suppose we look at a photograph of many galaxies. Assuming that all galaxies formed at about the same time, which galaxy in the picture is the youngest? A) the one that is farthest away B) the one that is reddest in color C) the one that is bluest in color D) the one that is closest to us E) the one that appears smallest in size
The one that is farthest away.
question
What do we mean by the observable universe? A) the part of the universe that we can see with the naked eye B) the part of the universe that we can see through telescopes C) the part of the universe that could be observed in principle, including things that may require future technologies D) the compendium of all objects that we have observed to date E) the entire universe, since it is inconceivable that there could be parts of the universe that we cannot observe
The part of the universe that could be observed in principle, including things that may require future technologies.
question
What is the Sun mainly made of? A) hydrogen and oxygen B) hydrogen and helium C) carbon and nitrogen D) oxygen and carbon E) nearly equal portions of all the elements
Hydrogen and helium.
question
On the 1-to-10-billion scale, about how far is it to the nearest stars besides the Sun? A) 4 kilometers B) 400 kilometers C) 1,000 kilometers D) 4,400 kilometers E) 10,000 kilometers
4,400 kilometers.
question
Suppose we imagine the Sun to be about the size of a grapefruit. How far away are the nearest stars (the three stars of Alpha Centauri)? A) the length of a football field B) 2.5 miles C) 250 miles D) 2,500 miles E) 25,000 miles
2,500 miles.
question
If we use 1 millimeter to represent 1 light-year, how large in diameter is the Milky Way Galaxy? A) 100 millimeters B) 100 meters C) 1 kilometer D) 100 kilometers E) 1 million millimeters
100 meters
question
What best describes the Milky Way Galaxy? A) a spiral galaxy with a disk about 100,000 light-years in diameter and containing between 100 billion and 1 trillion stars B) a spiral galaxy with a disk about 1 billion kilometers in diameter and containing between 100 million and 1 billion stars C) a spiral galaxy with a disk about 100,000 light-years in diameter and containing about 100,000 stars D) a spherically shaped collection of stars including our solar system and about a dozen other solar systems, stretching about 4 light-years in diameter E) a spherically shaped collection of about 1 million stars that is about 100 light-years in diameter
A spiral galaxy with a disk about 100,000 light-years in diameter and containing between 100 billion and 1 trillion stars.
question
How long would it take to count all the stars in the Milky Way Galaxy at a rate of one star per second? A) several days B) several weeks C) several years D) several thousand years E) hundreds of thousands of years
Several thousand years.
question
How many galaxies are there in the observable universe? A) roughly (within a factor of 10) the same as the number of stars in our galaxy B) roughly a thousand times more than the number of stars in our galaxy C) about as many as the number of stars we see in the sky with our naked eyes D) about as many as the number of grains of sand on all the beaches on Earth E) an infinite number
Roughly (within a factor of 10) the same as the number of stars in our galaxy.
question
If you represented each star by a grain of sand, how much sand would it take to represent all the stars in the universe? A) all the sand in a typical playground sandlot B) all the sand on Miami Beach C) all the sand on the beaches of California D) all the sand on the beaches in the United States E) more than all the sand on all the beaches on Earth
More than all the sand on all the beaches on Earth.
question
On the scale of the cosmic calendar, in which the history of the universe is compressed to 1 year, how long has human civilization (i.e., since ancient Egypt) existed? A) about half the year B) about a month C) a few hours D) a few seconds E) less than a millionth of a second
A few seconds.
question
On a cosmic calendar, in which the history of the universe is compressed into 1 year, when did the dinosaurs become extinct? A) in late December B) in late November C) in late October D) in late September E) in late August
In late December.
question
On a cosmic calendar, in which the history of the universe is compressed into 1 year, when did Kepler and Galileo first discover that we live on a planet in a solar system? A) 1 second ago B) 1 day ago C) 1 week ago D) December 25 E) December 30
1 second ago.
question
On a cosmic calendar, in which the history of the universe is compressed into one year, how long is the average human life span? A) 0.2 millisecond B) 0.2 second C) 2 seconds D) 2 minutes E) 2 hours
0.2 second.
question
Approximately how fast are you moving with the rotation of Earth? A) 13,000 km/hr B) 1,300 km/hr C) 130 km/hr D) 13 km/hr E) not moving at all
1,300 km/hr.
question
What is an astronomical unit? A) the average speed of Earth around the Sun B) the length of time it takes Earth to revolve around the Sun C) the average distance from Earth to the Sun D) the diameter of Earth's orbit around the Sun E) any basic unit used in astronomy
The average distance from Earth to the Sun.
question
Which of the following is not true about the ecliptic plane? A) It is the plane of Earth's orbit around the Sun. B) It is the plane of the Moon's orbit around Earth. C) During a solar eclipse, the Moon lies in the ecliptic plane. D) During a lunar eclipse, the Moon lies in the ecliptic plane. E) The nodes of the Moon's orbit lie in the ecliptic plane.
It is the plane of the Moon's orbit around Earth.
question
Patterns of stars in constellations hardly change in appearance over times of even a few thousand years. Why? A) Stars are fixed and never move. B) Stars move, but they move very slowly-only a few kilometers in a thousand years. C) Although most stars move through the sky, the brightest stars do not, and these are the ones that trace the patterns we see in the constellations. D) The stars in our sky actually move rapidly relative to us-thousands of kilometers per hour- but are so far away that it takes a long time for this motion to make a noticeable change in the patterns in the sky. E) Stars within a constellation move together as a group, which tends to hide their actual motion and prevent the pattern from changing.
The stars in our sky actually move rapidly relative to us-thousands of kilometers per hour- but are so far away that it takes a long time for this motion to make a noticeable change in the patterns in the sky.
question
How long does it take our solar system to complete one orbit around the Milky Way Galaxy? A) 10 thousand years B) 230 thousand years C) 1 million years D) 100 million years E) 230 million years
230 million years.
question
What is not true about the Milky Way Galaxy? A) It contains between 100 billion and 1 trillion stars. B) Our solar system is located very close to the center of the Milky Way Galaxy. C) Our view of distant objects is obscured by gas and dust when we look into the galactic plane. D) The galaxy is about 100,000 light-years in diameter. E) One rotation of the galaxy takes about 200 million years.
Our solar system is located very close to the centre of the Milky Way Galaxy.
question
Which of the following correctly lists speeds from slowest to fastest? A) Earth's speed of revolution about the Sun, typical speeds of stars in the local solar neighborhood relative to us, Earth's speed of rotation on its axis, the speed of our solar system orbiting the center of the Milky Way Galaxy, the speeds of very distant galaxies relative to us B) Earth's speed of rotation on its axis, Earth's speed of revolution about the Sun, typical speeds of stars in the local solar neighborhood relative to us, the speed of our solar system orbiting the center of the Milky Way Galaxy, the speeds of very distant galaxies relative to us C) the speeds of very distant galaxies relative to us, typical speeds of stars in the local solar neighborhood relative to us, Earth's speed of rotation on its axis, Earth's speed of revolution about the Sun, the speed of our solar system orbiting the center of the Milky Way Galaxy D) the speed of our solar system orbiting the center of the Milky Way Galaxy, Earth's speed of revolution about the Sun, Earth's speed of rotation on its axis, the speeds of very distant galaxies relative to us, typical speeds of stars in the local solar neighborhood relative to us E) Earth's speed of revolution about the Sun, Earth's speed of rotation on its axis, the speed of our solar system orbiting the center of the Milky Way Galaxy, typical speeds of stars in the local solar neighborhood relative to us, the speeds of very distant galaxies relative to us
Earth's speed of rotation on its axis, Earth's speed of revolution about the Sun, typical speeds of stars in the local solar neighbourhood relative to us, the speed of our solar system orbiting the center of the Milky Way Galaxy, the speeds of very distant galaxies relative to us.
question
Most of the mass in the Milky Way Galaxy is located: A) in the halo (above/below the disk). B) within the disk. C) in the stars in the spiral arms. D) in the gas and dust. E) in the central bulge of the galaxy.
In the halo (above/below the disk).
question
The distribution of the mass of the Milky Way Galaxy is determined by: A) counting the number of stars. B) determining the amount of gas and dust. C) studying how stars are distributed in the Milky Way. D) studying the rotation of the galaxy. E) weighing various parts of the Milky Way.
Studying the rotation of the galaxy.
question
From the fact that virtually every galaxy is moving away from us and more distant galaxies are moving away from us at a faster rate than closer ones, we conclude that: A) the Milky Way Galaxy is expanding. B) we are located at the center of the universe. C) the farthest galaxies will eventually be moving faster than the speed of light. D) the universe is expanding. E) the universe is shrinking.
The universe is expanding.
question
How do we know our universe is expanding? A) All galaxies contain billions of stars, and all galaxies have spiral shapes. B) All galaxies were born at the same time, and all will die at the same time. C) All galaxies outside the Local Group are moving away from us, and the farther away they are, the faster they're going. D) All galaxies outside the Local Group are orbiting the Local Group. E) All galaxies outside the Local Group are moving away from us, and all are moving away at nearly the same speed.
All galaxies outside the Local Group are moving away from us, and the farther away they are, the faster they're going.
question
Which scientists played a major role in overturning the ancient idea of an Earth-centered universe, and about when? A) Copernicus, Kepler, and Galileo; about 400 years ago B) Aristotle and Copernicus; about 400 years ago C) Newton and Einstein; about 100 years ago D) Huygens and Newton; about 300 years ago E) Aristotle and Plato; about 2,000 years ago
Copernicus, Kepler, and Galileo; about 400 years ago.
question
(T/F) Our solar system is located in the center of the Milky Way Galaxy.
False.
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(T/F) The solar system contains about 100 billion stars.
False.
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(T/F) A typical supercluster contains no more than about 10,000 stars.
False.
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(T/F) One light-year is about 10 trillion kilometers.
True.
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(T/F) In the grapefruit model of the solar system, it would take a few minutes to walk from the Sun to the inner edge of the Kuiper Belt (Pluto).
True.
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(T/F) The observable universe is the same size today as it was a few billion years ago.
False.
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(T/F) The Milky Way is moving further away from most other galaxies in the Universe.
True.
question
(T/F) No galaxies existed before the Big Bang.
True.
question
(T/F) Voyager 2 should reach the nearest stars (besides the Sun) in about 500 years.
False.
question
(T/F) Earth is always precisely 1 AU from the Sun.
False.
question
Our solar system consists of: A) the Sun and all the objects that orbit it. B) the Sun and the planets, and nothing else. C) a few hundred billion stars, bound together by gravity. D) the Sun and several nearby stars, as well as the planets and other objects that orbit these stars.
The Sun and all the objects that orbit it.
question
A typical galaxy is a: A) collection of a few hundred million to a trillion or more stars, bound together by gravity. B) large, glowing ball of gas powered by nuclear energy. C) nearby object orbiting a planet. D) relatively small, icy object orbiting a star.
Collection of a few hundred million to a trillion or more stars, bound together by gravity.
question
What best describes the universe? A) the sum total of all matter and energy B) a vast collection of stars that number as many as the grains of sand on all the beaches on Earth C) all the galaxies in all the superclusters D) The universe is another name for our Milky Way Galaxy.
The sum total of all matter and energy.
question
What do astronomers mean by the Big Bang? A) the event that marked the beginning of the expansion of the universe B) a gigantic explosion that blew all the galaxies in the universe to smithereens C) the explosion of a massive star at the end of its life D) the event that marked the birth of our solar system
The event that marked the beginning of the expansion of the universe.
question
Based on observations of the universal expansion, the age of the universe is about: A) 14,000 years. B) 14 million years. C) 14 billion years. D) 14 trillion years.
14 billion years.
question
A television advertisement claiming that a product is light-years ahead of its time does not make sense because A) it doesn't specify the number of light-years. B) it uses "light-years" to talk about time, but a light-year is a unit of distance. C) a light-year is an astronomically large unit, so a product could not possibly be so advanced. D) light-years can only be used to talk about light.
It uses "light-years" to talk about time, but a light-year is a unit of distance.
question
On a scale in which the distance from Earth to the Sun is about 15 meters, the distance from Earth to the Moon is: A) small enough to fit within your hand. B) about 1 meter. C) about 5 meters. D) about 30 meters.
Small enough to fit within your hand.
question
On a scale where the Sun is about the size of a grapefruit and the Earth is about 15 meters away, how far away are the nearest stars besides the Sun? A) 100 meters B) about the distance across 50 football fields C) about the distance across the state of Delaware D) about the distance across the United States
About the distance across the United States.
question
The number of stars in the Milky Way Galaxy is approximately: A) a few hundred. B) a few hundred thousand. C) a few hundred billion. D) a few hundred million.
A few hundred billion.
question
What is the ecliptic plane? A) the plane of Earth's orbit around the Sun B) the plane of Earth's equator C) the plane of the Sun's equator D) the plane of the Milky Way Galaxy
The plane of Earth's orbit around the Sun.
question
How long does it take the Earth to complete one orbit around the Sun? A) one year B) one day C) one month D) one week E) The time it takes Earth to orbit the Sun changes significantly from one orbit to the next.
One year.
question
When we look at an object that is 1,000 light-years away we see it: A) as it was 1,000 years ago. B) as it was 1,000 light-years ago. C) as it is right now, but it appears 1,000 times dimmer. D) looking just the same as our ancestors would have seen it 1,000 years ago.
As it was 1,000 years ago.
question
Suppose we look at two distant galaxies: Galaxy 1 is twice as far away as Galaxy 2. In this case, A) Galaxy 1 must be twice as big as Galaxy 2. B) we are seeing Galaxy 1 as it looked at an earlier time in the history of the universe than Galaxy 2. C) we are seeing Galaxy 1 as it looked at a later time in the history of the universe than Galaxy 2. D) Galaxy 2 must be twice as old as Galaxy 1.
We are seeing Galaxy 1 as it looked at an earlier time in the history of the universe than Galaxy 2.
question
Suppose we make a scale model of our solar system, with the Sun the size of a grapefruit. Which of the following best describes what the planets would look like? A) The planets are all much smaller than the Sun. Four planets are within about 20 meters of the Sun, while the rest planets are spread much farther apart. B) The planets are all much smaller than the Sun and are spread out evenly over a distance about the length of a large classroom. C) The planets are all much smaller than the Sun. Four planets are located within a few centimeters of the Sun, and four planets are located at distances ranging up to about a meter. D) The planets range in size from about the size of a marble to the size of a baseball. They are spread out over a region about the size of a football field.
The planets are all much smaller than the Sun. Four planets are within about 20 meters of the Sun, while the rest planets are spread much farther apart.
question
If you could count stars at a rate of about one per second, how long would it take to count all the stars in the Milky Way Galaxy? A) several days B) several weeks C) several years D) several thousand years
Several thousand years
question
The total number of stars in the observable universe is about: A) 100 billion. B) the same as the number of grains of sand in a school sandbox. C) the same as the number of grains of sand on all the beaches on Earth. D) the same as the number of atoms that make up the Earth.
The same as the number of grains of sand on all the beaches on Earth.
question
If we imagine the history of the universe compressed into one year, dinosaurs became extinct: A) about 6 months ago. B) about 3 weeks ago. C) yesterday morning. D) about an hour ago.
Yesterday morning.
question
Relative to the age of the universe, how old is our solar system? A) It is about 1% as old as the universe. B) It is between about 5% and 10% as old as the universe. C) It is about one-third the age of the universe. D) It is nearly the same age as the universe.
It is about one-third the age of the universe.
question
How do the speeds at which we are moving with Earth's rotation and orbit compare to the speeds of more familiar objects? A) Earth's rotation carries most people around the axis faster than a commercial jet travels, and Earth's orbit carries us around the Sun faster than the Space Shuttle orbits Earth. B) Earth's rotation carries most people around the axis at about the speed of a commercial jet, and Earth's orbit carries us around the Sun at about the speed of a military jet. C) Earth's rotation carries most people around the axis at about the speed of a car on the freeway, and Earth's orbit carries us around the Sun at about the speed of a commercial jet. D) Earth's rotation carries most people around the axis at about the speed at which the Space Shuttle orbits Earth, and Earth's orbit carries us around the Sun at nearly the speed of light.
Earth's rotation carries most people around the axis faster than a commercial jet travels, and Earth's orbit carries us around the Sun faster than the Space Shuttle orbits Earth.
question
Why do the patterns of the stars in our sky look the same from year to year? A) because the stars in the constellations are so far away B) because the stars in the constellations are not moving C) because the stars in the constellations all move at the same speeds and in the same directions, so they don't change their relative positions D) because the stars in the constellations move so slowlyâ€”typically about the speed of a snailâ€” that their motions are not noticeable