Astronomy Unit 1
On a cosmic calendar, in which the history of the universe is compressed into one year, how long is the average human life span? 0.2 second 2 hours 2 minutes 2 seconds 0.2 millisecond
0.2 second
Absolute zero is 0° Kelvin. 273° Celsius. 0° Celsius. 32° Fahrenheit. 0° Fahrenheit.
0° Kelvin.
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.) 300,000 km 1.08 billion km 100 million km 18 million km 9.46 trillion km
1.08 billion km
Modern telescopes are capable of seeing bright galaxies up to about 10 billion light-years away. 1 million light-years away. 1 trillion light-years away. 10 million light-years away. 1 billion light-years away.
10 billion light-years away.
About where is our solar system located within the Milky Way Galaxy? 100 trillion 10 billion 100 million 100 billion 1 billion
100 billion
How many arcseconds are in 1°? 60 3,600 360 10,000 100
3,600
From Kepler's third law, an asteroid with an orbital period of 8 years lies at an average distance from the Sun equal to 16 astronomical units. 8 astronomical units. 2 astronomical units. 4 astronomical units. It depends on the asteroid's mass.
4 astronomical units.
On the 1-to-10-billion scale, about how far is it to the nearest stars besides the Sun? 4,400 kilometers 10,000 kilometers 400 kilometers 4 kilometers 1,000 kilometers
4,400 kilometers
If you drop a rock from a great height, about how fast will it be falling after 5 seconds, neglecting air resistance? It depends on what shape it is. 15 m/s 50 m/s It depends on how heavy it is. 10 m/s
50 m/s
According to what we now know from Newton's laws, which of the following best explains why Kepler's second law is true? Orbits must be elliptical in shape. A planet's angular momentum must be conserved as it moves around its orbit. Gravity is an inverse cube law. This effect happens because of the influence of other planets on a particular planet's orbit.
A planet's angular momentum must be conserved as it moves around its orbit.
By studying distant galaxies in the 1920s, Hubble made which of the following important discoveries that led us to conclude that the universe is expanding? All galaxies were born at the same time, and all will die at the same time. All galaxies outside the Local Group are moving away from us, and the farther away they are, the faster they're going. All galaxies contain billions of stars, and all galaxies have spiral shapes. 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 orbiting the Local Group.
All galaxies outside the Local Group are moving away from us, and the farther away they are, the faster they're going.
Why do we have seasons on Earth? As Earth goes around the Sun and Earth's axis remains pointed toward Polaris, the Northern and Southern hemispheres alternately receive more and less direct sunlight. The tilt of Earth's axis constantly changes between 0 and 23 1/2°, giving us summer when Earth is tilted more and winter when it is straight up. Seasons are caused by the influence of the planet Jupiter on our orbit. Earth's distance from the Sun varies, so that it is summer when we are closer to the Sun and winter when we are farther from the Sun.
As Earth goes around the Sun and Earth's axis remains pointed toward Polaris, the Northern and Southern hemispheres alternately receive more and less direct sunlight.
What do we mean when we say that the universe is expanding? The statement is not meant to be literal; rather, it means that our knowledge of the universe is growing. Average distances are increasing between galaxies. Everything in the universe is gradually growing in size. Individual galaxies are gradually growing in size. Average distances are increasing between star systems within galaxies.
Average distances are increasing between galaxies.
When Copernicus first created his Sun-centered model of the universe, it did not lead to substantially better predictions of planetary positions than the Ptolemaic model. Why not? Copernicus used perfect circles for the orbits of the planets. Copernicus placed the Sun at the center but did not realize that the Moon orbits Earth. Copernicus placed the planets in the wrong order going outward from the Sun. Copernicus misjudged the distances between the planets. Copernicus misjudged the speeds at which the planets orbit the Sun.
Copernicus used perfect circles for the orbits of the planets.
Which of the following correctly lists speeds from slowest to fastest? 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 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 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 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 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
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
Which of the following correctly lists our "cosmic address" from small to large? Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe Earth, solar system, Milky Way Galaxy, universe, Local Group, Local Supercluster Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe
Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe
How are galaxies important to our existence? Galaxies prevent planets from leaving their orbits around stars; e.g., our galaxy prevents Earth from leaving its orbit of the Sun. Galaxies provide the gravity that prevents us from falling off Earth. Galaxies recycle heavy elements produced in stars into future generations of stars. Without galaxies, there could not have been a Big Bang. Without galaxies, the universe could not be expanding.
Galaxies recycle heavy elements produced in stars into future generations of stars.
One of the "nails in the coffin" for Earth-centered universe was Galileo's observations of the moons of Jupiter. Galileo's observation of stars in the Milky Way. the phases of the Moon. eclipses of the Sun. the retrograde motion of the planets.
Galileo's observations of the moons of Jupiter.
What makes the North Star, Polaris, special? It is the brightest star in the sky. It appears very near the north celestial pole. It can be used to determine your longitude on Earth. It is the star straight overhead. It is the star directly on your northern horizon.
It appears very near the north celestial pole.
Earth is made mostly of metals and rocks. Where did this material come from? It was created by chemical reactions in interstellar space. It was produced by nuclear fusion in stars. It was made by our Sun. It was produced in the Big Bang. It was made by nuclear fission of uranium and other radioactive materials.
It was produced by nuclear fusion in stars.
What would happen if the Space Shuttle were launched with a speed greater than Earth's escape velocity? It would take less time to reach its bound orbit. It would be in an unstable orbit. It would orbit Earth at a faster velocity. It would travel in a higher orbit around Earth. It would travel away from Earth into the solar system.
It would travel away from Earth into the solar system.
He discovered that the orbits of planets are ellipses. Galileo Ptolemy Copernicus Kepler Tycho Brahe
Kepler
Which ancient culture had the greatest known success in predicting eclipses? Aztecs Babylonians Mayans Greeks Egyptians
Mayans
When we look into the band of light in our sky that we call the Milky Way, can we see distant galaxies? Why or why not? No, because the stars, gas, and dust of the Milky Way block us from seeing them. Yes, there are many other galaxies that we see inside the Milky Way. No, we cannot see any other galaxies from Earth. No, because there are only galaxies above and below the plane of the Milky Way. Yes, they appear as small, fuzzy patches on the other side of our galaxy.
No, because the stars, gas, and dust of the Milky Way block us from seeing them.
He developed a system for predicting planetary positions that remained in use for some 1,500 years. Galileo Ptolemy Copernicus Tycho Brahe Kepler
Ptolemy
Which of the following statements about the celestial sphere is not true? From any location on Earth, we can see only half the celestial sphere at any one time. Earth is placed at the center of the celestial sphere. The celestial sphere does not exist physically. The "celestial sphere" is just another name for our universe. When we look in the sky, the stars all appear to be located on the celestial sphere.
The "celestial sphere" is just another name for our universe.
Suppose a lone asteroid happens to be passing relatively near Jupiter (but not near any of its moons), following a hyperbolic orbit as it approaches Jupiter. Which of the following statements would be true? Jupiter's gravity would capture the asteroid, making it a new moon of Jupiter. Jupiter would probably expel the asteroid far out into the solar system. The asteroid would slowly spiral into Jupiter until it crashed into the atmosphere. The asteroid's orbit around Jupiter would not change, and it would go out on the same hyperbolic orbit that it came in on. Any of these scenarios is possible.
The asteroid's orbit around Jupiter would not change, and it would go out on the same hyperbolic orbit that it came in on.
What conditions are required for a solar eclipse? The phase of the Moon must be new, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun. The phase of the Moon can be new or full, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun. The phase of the Moon must be full, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun. The phase of the Moon must be full, and the Moon's orbital plane must lie in the ecliptic. The phase of the Moon must be new, and the Moon's orbital plane must lie in the ecliptic.
The phase of the Moon must be new, and the nodes of the Moon's orbit must be nearly aligned with Earth and the Sun.
Why were ancient peoples unable to detect stellar parallax? They did not observe for long enough periods of time. They did detect it, but they rejected the observations. They did not have the ability to measure very small angles. They could not see distant stars. They did not look for it.
They did not have the ability to measure very small angles.
He was the first to prove that comets lie beyond Earth's atmosphere. Kepler Galileo Tycho Brahe Aristotle Copernicus
Tycho Brahe
Which of the following statements is not one of Newton's laws of motion? For any force, there always is an equal and opposite reaction force. The rate of change of momentum of an object is equal to the net force applied to the object. What goes up must come down. In the absence of a net force, an object moves with constant velocity. All of the above are Newton's laws of motion.
What goes up must come down.
How many stars can you see with your naked eye on a clear, moonless night from a dark location? about ten thousand more than you could count in your lifetime a few thousand fewer than a thousand about a hundred thousand
a few thousand
What is meant by a scientific paradigm? a historical theory that has been proved inaccurate a radical change in scientific thought a conundrum or unexplained set of facts a pseudoscientific idea a generally well-established scientific theory or set of theories
a generally well-established scientific theory or set of theories
Kepler's second law, which states that as a planet moves around its orbit it sweeps out equal areas in equal times, means that planets that are farther from the Sun move at slower average speeds than nearer planets. a planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun. the period of a planet does not depend on its mass. a planet's period does not depend on the eccentricity of its orbit. planets have circular orbits.
a planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun.
Which of the following best describes the Milky Way Galaxy? a spherically shaped collection of stars including our solar system and about a dozen other solar systems, stretching about 4 light-years in diameter a spiral galaxy with a disk about 100,000 light-years in diameter and containing about 100,000 stars a spherically shaped collection of about 1 million stars that is about 100 light-years in diameter a spiral galaxy with a disk about 1 billion kilometers in diameter and containing between 100 million and 1 billion stars a spiral galaxy with a disk about 100,000 light-years in diameter and containing between 100 billion and 1 trillion stars
a spiral galaxy with a disk about 100,000 light-years in diameter and containing between 100 billion and 1 trillion stars
What is meant by a hypothesis? a historical theory that has been proved inaccurate a natural phenomenon that requires explanation an explanation for a phenomenon that makes a prediction a pseudoscientific idea a tentative understanding of a natural phenomenon
an explanation for a phenomenon that makes a prediction
Why do we see essentially the same face of the Moon at all times? because the Moon has a nearly circular orbit around Earth because the Moon's rotational and orbital periods are equal because the other face points toward us only at new Moon, when we can't see the Moon because the Moon does not rotate because the Sun illuminates only one half at a time
because the Moon's rotational and orbital periods are equal
The age of the universe is between 100 million and 160 million years. between 10 billion and 16 billion years. between 10 million and 16 million years. between 100 billion and 160 billion years. between 1 billion and 1.6 billion years.
between 10 billion and 16 billion years.
The astrology practiced by those who cast predictive horoscopes can be tested by asking astronomers if it works. polling people to find out what percentage believe their horoscopes to be accurate. counting how many times the predictions come true. comparing how often the predictions come true to what would be expected by pure chance. asking astrologers if it works.
comparing how often the predictions come true to what would be expected by pure chance.
Suppose an object is moving in a straight line at 50 miles/hr. According to Newton's first law of motion, the object will continue to move in a straight line forever if it is in space, but slow and stop otherwise. eventually slow down and come to a stop. continually slow down but never quite come to a complete stop. continue to move in the same way forever, no matter what happens. continue to move in the same way until it is acted upon by a force.
continue to move in the same way until it is acted upon by a force.
If it is midnight in New York, it is midday in Rio de Janeiro, Brazil. midnight everywhere. midnight in Los Angeles. daytime in Sydney, Australia. midnight in Sydney, Australia.
daytime in Sydney, Australia.
Ptolemy was important in the history of astronomy because he was the first to believe in an Earth-centered universe. developed a scientifically accurate model of the universe. was the first to create a model of the solar system that placed the Sun rather than Earth at the center. developed a model of the solar system that made sufficiently accurate predictions of planetary positions to remain in use for many centuries. was the first to believe that all orbits are perfect circles.
developed a model of the solar system that made sufficiently accurate predictions of planetary positions to remain in use for many centuries.
Which of the following is an example in which you are traveling at constant speed but not at constant velocity? jumping up and down, with a period of exactly 60 hops per minute driving around in a circle at exactly 100 km/hr none of the above driving backward at exactly 50 km/hr rolling freely down a hill in a cart, traveling in a straight line
driving around in a circle at exactly 100 km/hr
Radiative energy is energy used to power home radiators. energy of motion. heat energy. energy from nuclear power plants. energy carried by light.
energy carried by light.
Which of the following is a form of electrical potential energy? moving blades on an electric mixer energy from the Sun light from a fluorescent bulb energy coming to your house from power companies coal
energy coming to your house from power companies
Which of the following is not a phase of the Moon? third-quarter Moon first-quarter Moon half Moon new Moon full Moon
half Moon
What is the Sun mainly made of? hydrogen and oxygen oxygen and carbon nearly equal portions of all the elements hydrogen and helium carbon and nitrogen
hydrogen and helium
According to the universal law of gravitation, the force due to gravity is directly proportional to the distance between objects. inversely proportional to the square of the distance between objects. inversely proportional to the distance between objects. directly proportional to the square of the distance between objects. not dependent on the distance between objects.
inversely proportional to the square of the distance between objects.
Newton's second law of motion tells us that the net force applied to an object equals its mass times energy. momentum times velocity. mass times velocity. energy times acceleration. mass times acceleration.
mass times acceleration.
What quantities does angular momentum depend upon? mass, velocity, and radius momentum and angular velocity force and radius force, velocity, and radius mass and velocity
mass, velocity, and radius
The mass of Jupiter can be calculated by measuring the orbital period and distance of one of Jupiter's moons. measuring the orbital speed of one of Jupiter's moons. measuring the orbital period and distance of Jupiter's orbit around the Sun. knowing the Sun's mass and measuring how Jupiter's speed changes during its elliptical orbit around the Sun. knowing the Sun's mass and measuring the average distance of Jupiter from the Sun.
measuring the orbital period and distance of one of Jupiter's moons.
At approximately what time would a first quarter Moon rise? midnight 9 A.M. noon. 6 A.M. 6 P.M.
noon
How many galaxies are there in the observable universe? an infinite number about as many as the number of grains of sand on all the beaches on Earth about as many as the number of stars we see in the sky with our naked eyes roughly a thousand times more than the number of stars in our galaxy roughly (within a factor of 10) the same as the number of stars in our galaxy
roughly (within a factor of 10) the same as the number of stars in our galaxy
The names of the seven days of the week are based on the seven planets closest to the Sun. seven brightest stars in the prominent constellation Orion. most popular Norse gods. seven naked-eye objects that appear to move among the constellations. seven largest constellations of the ancient world.
seven naked-eye objects that appear to move among the constellations.
Which of the following is smallest? 1 AU size of a typical planet 1 light-second size of a typical star
size of a typical planet
In order to tell time at night, the ancient Egyptians of 3000 B.C. used Moon clocks, which measured time based on the Moon's position relative to the stars. star clocks, which measured time based on the positions of stars at particular times of night and particular times of year. water clocks, measuring the flow of water through an opening. sundials, with light provided by the Moon. hourglasses, measuring the flow of sand through an opening.
star clocks, which measured time based on the positions of stars at particular times of night and particular times of year.
Apparent retrograde motion is an illusion created by turbulence in Earth's atmosphere. Mars Venus Jupiter Saturn the Sun
the Sun
What is an astronomical unit? the length of time it takes Earth to revolve around the Sun the average distance from Earth to the Sun the average speed of Earth around the Sun the diameter of Earth's orbit around the Sun any basic unit used in astronomy
the average distance from Earth to the Sun
What does temperature measure? the total potential energy of particles in a substance the average mass of particles in a substance the average kinetic energy of particles in a substance the average size of particles in a substance the total number of particles in a substance
the average kinetic energy of particles in a substance
The precession of the Moon's nodes means that there is a solar eclipse every 6 months. the vernal equinox will be in Aquarius in a few hundred years. there is a lunar eclipse every 6 months. the eclipse seasons occur less than 6 months apart. there are never two solar eclipses in the same year.
the eclipse seasons occur less than 6 months apart.
If the Moon is rising at midnight, the phase of the Moon must be third quarter. waning crescent. waxing crescent. first quarter. full.
third quarter.
In which of the following cases would you feel weightless? none of the above while falling from an airplane with your parachute open while falling from a roof while traveling through space in an accelerating rocket while walking on the Moon
while falling from a roof
