Term
| Suppose you live in the United States and you see a crescent moon in your evening sky tonight. What will a friend in South America see tonight? |
|
Definition
| Your friend will see a crescent moon. |
|
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Term
| The path that led to modern science emerged from ancient civilizations in which part of the world? |
|
Definition
| the Mediterranean and the Middle East |
|
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Term
| Galileo observed all of the following. Which observation offered direct proof of a planet orbiting the Sun? |
|
Definition
|
|
Term
| When traveling north from the United States into Canada, you'll see the North Star (Polaris) getting |
|
Definition
|
|
Term
| Which of the following best describes how modern astronomers view astrology? |
|
Definition
| Astrology played an important part in the development of astronomy in ancient times, but it is not a science by modern standards. |
|
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Term
| The ancient Greeks get a lot of attention for their contributions to science because |
|
Definition
| they were the first people known to try to explain nature with models based on reason, mathematics, and geometry, without resort to the supernatural. |
|
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Term
| The great contribution of Tycho Brahe was to |
|
Definition
| observe planetary positions with sufficient accuracy so that Kepler could later use the data to discover the laws of planetary motion. |
|
|
Term
| Which of the following is smallest? |
|
Definition
|
|
Term
| Based on observations of the universal expansion, the age of the universe is about |
|
Definition
|
|
Term
| When we see Venus in its full phase, what phase would Earth be in as seen by a hypothetical Venetian? |
|
Definition
|
|
Term
| In any particular place on Earth, certain constellations are visible in the evening only at certain times of the year because |
|
Definition
| our evening view of space depends on where Earth is located in its orbit around the Sun. |
|
|
Term
| During the period each year when we see Mars undergoing apparent retrograde motion in our sky, what is really going on in space? |
|
Definition
| Earth is catching up with and passing by Mars in their respective orbits. |
|
|
Term
| Our solar system consists of |
|
Definition
| the sun and all the objects that orbits it |
|
|
Term
| Suppose you see a photo showing Jupiter half in sunlight and half in shadow (that is, a first quarter Jupiter). This photo might have been taken by |
|
Definition
| the Hubble Space Telescope (which orbits Earth) |
|
|
Term
| When we look at an object that is 1,000 light-years away, we see it |
|
Definition
| as it was 1,000 years ago |
|
|
Term
| How does Earth's varying distance from the Sun affect our seasons? |
|
Definition
| It doesn't—Earth's orbital distance plays no obvious role in the seasons. |
|
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Term
| What do the structures of Stonehenge, the Templo Mayor, the Sun Dagger, and the Big Horn Medicine Wheel all have in common? |
|
Definition
| They were all used by ancient peoples for astronomical observations. |
|
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Term
| He discovered that the orbits of planets are ellipses. |
|
Definition
|
|
Term
| How long does it take Earth to complete one orbit around the Sun? |
|
Definition
|
|
Term
| Which of the following statements does not use the term light-year in an appropriate way? |
|
Definition
| It will take me light-years to complete this homework assignment. |
|
|
Term
| What is the ecliptic plane? |
|
Definition
| The plane of Earth's orbit around the Sun |
|
|
Term
| Which of the following has your "cosmic address" in the correct order? |
|
Definition
| you, Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe |
|
|
Term
| For most of history, the lack of observable stellar parallax was interpreted to mean that |
|
Definition
| Earth is stationary at the center of the universe. |
|
|
Term
| How did the Ptolemaic model explain the apparent retrograde motion of the planets? |
|
Definition
| It held that the planets moved along small circles that moved on larger circles around Earth, and that the combined motion sometimes resulted in backward motion. |
|
|
Term
| What is a circumpolar star? |
|
Definition
| a star that always remains above your horizon |
|
|
Term
| How many galaxies are there in the observable universe? |
|
Definition
| roughly (within a factor of 10) the same as the number of stars in our galaxy |
|
|
Term
| Each part below describes how a few astronomical phenomena are related to time periods. Which list is correct? (Careful: some lists are partially correct.) |
|
Definition
A)Earth's rotation defines a day.
The cycle of the Moon's phases takes about a month.
Earth's orbit defines a year.
Earth's cycle of axis precession takes 26,000 years. |
|
|
Term
| Only one of the statements below uses the term theory in its correct scientific sense. Which one? |
|
Definition
| Einstein's theory of relativity has been tested and verified thousands of times. |
|
|
Term
| What do astronomers mean by the Big Bang? |
|
Definition
| the event that marked the beginning of the expansion of the universe |
|
|
Term
| How many arcseconds are in 1°? |
|
Definition
|
|
Term
| Betelgeuse is the bright red star representing the left shoulder of the constellation Orion. All the following statements about Betelgeuse are true. Which one can you infer from its red color? |
|
Definition
| Its surface is cooler than the surface of the Sun |
|
|
Term
| According to our present theory of solar system formation, why were solid planetesimals able to grow larger in the outer solar system than in the inner solar system? |
|
Definition
| Because only metal and rock could condense in the inner solar system, while ice also condensed in the outer solar system. |
|
|
Term
| Based on everything you have learned in this chapter, which of the following statements seems unlikely to be true? |
|
Definition
| Only a tiny percentage of stars are surrounded by spinning disks of gas during their formation. |
|
|
Term
| Which of the following statements about X rays and radio waves is not true? |
|
Definition
| X rays travel through space faster than radio waves. |
|
|
Term
| Which planet has a ring system? |
|
Definition
|
|
Term
| Which of the following is not a major difference between the terrestrial and jovian planets in our solar system? |
|
Definition
| Terrestrial planets contain large quantities of ice and jovian planets do not. |
|
|
Term
| According to our theory of solar system formation, which law best explains why the solar nebula spun faster as it shrank in size? |
|
Definition
| the law of conservation of angular momentum |
|
|
Term
| When a spinning ice skater pulls in his arms, he spins faster because |
|
Definition
| his angular momentum must be conserved, so reducing his radius must increase his speed of rotation. |
|
|
Term
| Newton showed that Kepler's laws are |
|
Definition
| natural consequences of the law of universal gravitation. |
|
|
Term
| Where did the elements heavier than hydrogen and helium come from? |
|
Definition
| They were produced inside stars. |
|
|
Term
| Each of the following describes an "Atom 1" and an "Atom 2." In which case are the two atoms different isotopes of the same element? |
|
Definition
B)Atom 1: nucleus with 7 protons and 8 neutrons, surrounded by 7 electrons.
Atom 2: nucleus with 7 protons and 7 neutrons, surrounded by 7 electrons. |
|
|
Term
| We can see each other in the classroom right now because we |
|
Definition
|
|
Term
| We can see each other in the classroom right now because we |
|
Definition
|
|
Term
| We can see each other in the classroom right now because we |
|
Definition
|
|
Term
| Suppose you kick a soccer ball straight up to a height of 10 meters. Which of the following is true about the gravitational potential energy of the ball during its flight? |
|
Definition
| The ball's gravitational potential energy is greatest at the instant when the ball is at its highest point. |
|
|
Term
| we observe one edge of a planet to be redshifted and the opposite edge to be blueshifted, what can we conclude about the planet? |
|
Definition
|
|
Term
| Which of the following represents a case in which you are not accelerating? |
|
Definition
| driving in a straight line at 60 miles per hour |
|
|
Term
| Which of the following conditions lead you to see an absorption line spectrum from a cloud of gas in interstellar space? |
|
Definition
| The cloud is cool and lies between you and a hot star. |
|
|
Term
| In what way is Venus most similar to Earth? |
|
Definition
| both planets are nearly the same size. |
|
|
Term
| Which of the following is not evidence supporting the idea that our Moon formed as a result of a giant impact? |
|
Definition
| The Pacific Ocean appears to be a large crater—probably the one made by the giant impact. |
|
|
Term
| Which of the following best describes the origin of ocean tides on Earth? |
|
Definition
| Tides are caused by the difference in the force of gravity exerted by the Moon across the sphere of Earth. |
|
|
Term
| Which of the following statements is not one of Newton's laws of motion? |
|
Definition
| What goes up must come down. |
|
|
Term
| The acceleration of gravity on Earth is approximately 10 m/s2 (more precisely, 9.8 m/s2). If you drop a rock from a tall building, about how fast will it be falling after 3 seconds? |
|
Definition
|
|
Term
| Suppose you drop a 10-pound weight and a 5-pound weight on the Moon, both from the same height at the same time. What will happen? |
|
Definition
| Both will hit the ground at the same time |
|
|
Term
| Suppose that Star X and Star Y both have redshifts, but Star X has a larger redshift than Star Y. What can you conclude? |
|
Definition
| Star X is moving away from us faster than Star Y. |
|
|
Term
| Suppose you start with 1 kilogram of a radioactive substance that has a half-life of 10 years. Which of the following statements will be true after 20 years pass? |
|
Definition
| You'll have 0.25 kilogram of the radioactive substance remaining. |
|
|
Term
| The wavelength of a wave is |
|
Definition
| the distance between two adjacent peaks of the wave. |
|
|
Term
| According to the universal law of gravitation, if you triple the distance between two objects, then the gravitational force between them |
|
Definition
| decreases by a factor of 9. |
|
|
Term
| How does the light-collecting area of an 8-meter telescope compare to that of a 2-meter telescope? |
|
Definition
| The 8-meter telescope has 16 times the light-collecting area of the 2-meter telescope. |
|
|
Term
| Where are most of the known asteroids found? |
|
Definition
| between the orbits of Mars and Jupiter |
|
|
Term
| When a rock is held above the ground, we say it has some potential energy. When we let it go, it falls and we say the potential energy is converted to kinetic energy. Finally, the rock hits the ground (and stays there). What has happened to the energy? |
|
Definition
| The energy goes to producing sound and to heating the ground, rock and surrounding air. |
|
|
Term
| Which of the following is not an advantage of the Hubble Space Telescope over ground-based telescopes? |
|
Definition
| It is closer to the stars. |
|
|
Term
| What do we mean when we say that the Sun is in gravitational equilibrium? |
|
Definition
| There is a balance within the Sun between the outward push of pressure and the inward pull of gravity. |
|
|
Term
| The Sun's average surface (photosphere) temperature is about |
|
Definition
|
|
Term
| The Sun's surface seethes and churns with a bubbling pattern. Why? |
|
Definition
| We are seeing hot gas rising and cool gas falling due to the convection that occurs beneath the surface. |
|
|
Term
| The overall result of the proton-proton chain is: |
|
Definition
|
|
Term
| Every second, the Sun converts 600 million tons of hydrogen into 596 million tons of helium. The remaining 4 million tons |
|
Definition
| are converted to an amount of energy equal to 4 million tons times the speed of light squared. |
|
|
Term
| Why do sunspots appear dark in pictures of the Sun? |
|
Definition
| They actually are fairly bright, but appear dark against the even brighter background of the surrounding photosphere. |
|
|
Term
| According to modern science, approximately how old is the Sun? |
|
Definition
|
|
Term
| Why are neutrinos so difficult to detect? |
|
Definition
| They have a tendency to pass through just about any material without any interactions. |
|
|
Term
| To estimate the central temperature of the Sun, scientists |
|
Definition
| use computer models to predict interior conditions. |
|
|
Term
| What do sunspots, solar prominences, and solar flares all have in common? |
|
Definition
| The are all strongly influenced by magnetic fields on the Sun. |
|
|
Term
| All stars are born with the same basic composition, yet stars can look quite different from one another. Which two factors primarily determine the innate characteristics of a star? |
|
Definition
| its mass and its stage of life |
|
|
Term
| Which of the following statements about spectral types of stars is not generally true? |
|
Definition
| The spectral type of a star can be used to determine its distance. |
|
|
Term
| The choices below each describe the appearance of an H-R diagram for a different star cluster. Which cluster is the youngest? |
|
Definition
| The diagram shows main-sequence stars of every spectral type except O, along with a few giants and supergiants. |
|
|
Term
| If Star A is close to us than Star B, then Star A's parallax angle is |
|
Definition
| larger than that of Star B |
|
|
Term
| How is the lifetime of a star related to its mass? |
|
Definition
| More massive stars live considerably shorter lives than less massive stars. |
|
|
Term
| What is the common trait of all main sequence stars? |
|
Definition
| They generate energy through hydrogen fusion in their core. |
|
|
Term
|
Definition
| It is the remains of a star that no longer produces energy by nuclear fusion. |
|
|
Term
| Consider a large molecular cloud that will give birth to a cluster of stars. Which of the following would you expect to be true? |
|
Definition
| A few massive stars will form, live, and die before the majority of the star's clusters even complete their protostar stage. |
|
|
Term
| We do not know for certain whether the general trends we observe in stellar birth weights also apply to brown dwarfs. But if they do, then which of the following would be true? |
|
Definition
| Brown dwarfs would outnumber all ordinary stars. |
|
|
Term
| What will happen to the star after stage viii? |
|
Definition
| Its outer layers will be ejected as a planetary nebula and its core will become a white dwarf. |
|
|
Term
| Which of the following statements about various stages of core nuclear burning (hydrogen, helium, carbon, etc.) in a high-mass star is not true? |
|
Definition
| Each successive stage lasts for approximately the same amount of time. |
|
|
Term
|
Definition
| a star that is still in the process of forming |
|
|
Term
|
Definition
| The CNO cycle is a series of nuclear reactions that result overall in the fusion of four hydrogen nuclei into one helium nucleus. |
|
|
Term
| No stars have been found with masses greater than 100 times our Sun because |
|
Definition
| they would generate so much power that they would blow themselves apart. |
|
|
Term
| Which of the following statements about degeneracy pressure is not true? |
|
Definition
| Degeneracy pressure varies with the temperature of the star. |
|
|
Term
| What do we mean by the event horizon of a black hole? |
|
Definition
| It is the point beyond which neither light nor anything else can escape the black hole's gravity. |
|
|
Term
| What does cosmological redshift do to light? |
|
Definition
| stretches it in wavelength |
|
|
Term
| Which of the following phenomena are not thought to be results of collisions or other interactions between galaxies? |
|
Definition
| the fact that spiral galaxies have both disk and halo components |
|
|
Term
| Why are white-dwarf supernovae more useful for measuring cosmic distances than massive-star supernovae? |
|
Definition
| White-dwarf supernovae all have roughly the same true peak luminosity, while massive-star supernovae come in a wide range of peak luminosities. |
|
|
Term
| How can we see through the interstellar medium? |
|
Definition
| by observing in high-energy wavelengths such as X rays and long wavelengths of light such as radio waves |
|
|
Term
| Imagine that our Sun were magically and suddenly replaced by a black hole of the same mass (1 solar mass). What would happen to Earth in its orbit? |
|
Definition
| Nothing—Earth's orbit would remain the same. |
|
|
Term
| What do we mean by a protogalactic cloud? |
|
Definition
| It is a cloud of matter that contracts to become a galaxy. |
|
|
Term
| Red and orange stars are found evenly spread throughout the galactic disk, but blue stars are typically found |
|
Definition
| only near star-forming regions. |
|
|
Term
| Which statement about pulsars is not thought to be true? |
|
Definition
| Pulsars can form only in close binary systems. |
|
|
Term
| The maximum mass of a white dwarf is |
|
Definition
| about 1.4 times the mass of our Sun. |
|
|
Term
| Which constellation lies in the direction toward the galactic center? |
|
Definition
|
|
Term
| Suppose you drop a clock toward a black hole. As you look at the clock from a high orbit, what will you notice? |
|
Definition
| Time on the clock will run slower as it approaches the black hole, and light from the clock will be increasingly redshifted. |
|
|
Term
| The most basic difference between elliptical galaxies and spiral galaxies is that |
|
Definition
| elliptical galaxies lack anything resembling the disk of a spiral galaxy. |
|
|
Term
| What do we mean by the star-gas-star cycle? |
|
Definition
| It is the continuous recycling of gas in the galactic disk between stars and the interstellar medium. |
|
|
Term
| The primary way that we observe the atomic hydrogen that makes up most of the interstellar gas in the Milky Way is with |
|
Definition
| radio telescopes observing at a wavelength of 21 centimeters. |
|
|
Term
| Which of the following features is not a feature of a central dominant galaxy? |
|
Definition
| They are often spiral galaxies |
|
|
Term
| According to present understanding, a nova is caused by |
|
Definition
| the fusion of hydrogen on the surface of a white dwarf. |
|
|
Term
| Current estimates place the age of the universe at about |
|
Definition
|
|
Term
| Where are most heavy elements made? |
|
Definition
|
|
Term
| Will our Sun ever undergo a white dwarf supernova explosion? Why or why not? |
|
Definition
| No, because it is not orbited by another star |
|
|
Term
| Most stars in the Milky Way's halo are |
|
Definition
|
|
Term
| What do we call the bright, sphere-shaped region of stars that lie within a few thousand light-years of the center of the Milky Way Galaxy? |
|
Definition
|
|
Term
| What does Hubble's law tell us? |
|
Definition
| the more distant a galaxy,the faster it is moving away from us. |
|
|
Term
| What strange object do we think lies in the center of the Milky Way Galaxy? |
|
Definition
| a more than 2 milleion-solar-mass black hole |
|
|
Term
| What strange object do we think lies in the center of the Milky Way Galaxy? |
|
Definition
| a more than 2 milleion-solar-mass black hole |
|
|
Term
| What strange object do we think lies in the center of the Milky Way Galaxy? |
|
Definition
| a more than 2 milleion-solar-mass black hole |
|
|
Term
| The more massive a white dwarf, the |
|
Definition
|
|
Term
| What do halo stars do differently from disk stars? |
|
Definition
| Halo stars orbit the galactic center with many different inclinations, while disk stars all orbit in nearly the same plane |
|
|
Term
| Suppose that we observe a souce of X-rays that varies substantially in brightness over a period of a few days. What can we conclude? |
|
Definition
| The X-ray souce is no more than a few light-days in diameter |
|
|
Term
| What is an accretion disk? |
|
Definition
| a disk of hot gas swirling rapidly around a white dwarf, a neutron star, or a black hole in a binary system. |
|
|
Term
| How does an accretion disk around a neutron star differ from an accretion disk around a white dwarf? |
|
Definition
| The accretion disk around a neutron star is much hotter and emits higher-energy radiation than the accretion disk around a white dwarf. |
|
|
Term
| In a photo like the Hubble Deep Field, we see galaxies in many different stages of their lives. In general, which glaxies are seen in the earliest (youngest) stages of their lives? |
|
Definition
| The galaxies that are farthest away |
|
|
Term
| Which of the following show evidence of ancient river beds? |
|
Definition
|
|
Term
| What is a primitive meteorite? |
|
Definition
| a piece of rock that is essentially unchanged since it first condensed and accreted in the solar nebula some 4.6 billion years ago |
|
|
Term
| Which direction do a comet's dust and plasma tails point? |
|
Definition
| generally away from the Sun |
|
|
Term
| Which statement is not true? |
|
Definition
| Objects in the Kuiper belt are made mostly of rock and metal. |
|
|
Term
| What is the most abundant gas in Titan's atmosphere? |
|
Definition
|
|
Term
| Which of the following worlds has the most substantial atmosphere? |
|
Definition
|
|
Term
| Pluto is different from the other outer planets in all of the following ways except which one? |
|
Definition
| Its surface temperature is very cold. |
|
|
Term
| Which of the following gases is not a significant ingredient of the jovian planet atmospheres? |
|
Definition
|
|
Term
| Which of the following does not have a major effect in shaping planetary surfaces? |
|
Definition
|
|
Term
| Why does the burning of fossil fuels increase the greenhouse effect on Earth? |
|
Definition
| Burning releases carbon dioxide into the atmosphere |
|
|
Term
| What mechanism is most responsible for generating the internal heat of Io that drives the volcanic activity? |
|
Definition
|
|
Term
| What kind of surface features may result from tectonics? |
|
Definition
all of the above
A)valleys
B)mountains
C)volcanos
D)cliffs |
|
|
Term
| When we see a meteor shower, it means that |
|
Definition
| Earth is crossing the orbit of a comet. |
|
|
Term
| Jupiter's colors come in part from its three layers of clouds. Which of the following is not the primary constituent of one of Jupiter's cloud layers? |
|
Definition
|
|
Term
| What atmospheric constituent is responsible for the blue color of Uranus and Neptune? |
|
Definition
|
|
Term
| What was the Shoemaker-Levy 9 impact? |
|
Definition
| the impact of a fragmented comet on Jupiter, carefully observed by astronomers when it occurred in 1994 |
|
|
Term
| Which of the following best describes convection? |
|
Definition
| It is the process in which warm material expands and rises while cool material contracts and falls. |
|
|
Term
| Processed meteorites with high metal content probably are |
|
Definition
| chunks of a larger asteroid that was shattered by a collision. |
|
|
Term
| Why is Saturn almost as big as Jupiter, despite its smaller mass? |
|
Definition
| Jupiter's greater mass compresses it more, thus increasing its density. |
|
|
Term
| Why is Saturn almost as big as Jupiter, despite its smaller mass? |
|
Definition
| Jupiter's greater mass compresses it more, thus increasing its density |
|
|
Term
| What are the conditions necessary for a terrestrial planet to have a strong magnetic field? |
|
Definition
| both a molten metallic core and reasonably fast rotation |
|
|
Term
| Which of the following statements about the moons of the jovian planets is not true? |
|
Definition
| The majority of the moons are large enough to be spherical in shape, while only a few have the more potato-like shapes of asteroids. |
|
|
Term
| Why does Jupiter have three distinct layers of clouds? |
|
Definition
| The three layers represent clouds made of gases that condense at different temperatures and therefore different altitudes. |
|
|
Term
| Why do asteroids and comets differ in composition? |
|
Definition
| Asteroids formed inside the frost line, while comets formed outside. |
|
|
Term
| Suppose you could float in space just a few meters above Saturn's rings. What would you see as you looked down on the rings? |
|
Definition
| countless icy particles, ranging in size from dust grains to large boulders |
|
|
Term
| Under what circumstances can differentiation occur in a planet? |
|
Definition
| The planet must have a molten interior. |
|
|
Term
| The most volcanically active body in our solar system is |
|
Definition
|
|
Term
| According to current ideas, Pluto is best explained as |
|
Definition
| one of the larger (if not the largest) Kuiper-belt comets. |
|
|
Term
| Which of the following gases absorbs ultraviolet light best? |
|
Definition
|
|
Term
| Which of the following describes erosion? |
|
Definition
| the wearing down or building up of geological features by wind, water, ice, and other phenomena of planetary weather |
|
|
Term
| When you see the bright flash of a meteor, what are you actually seeing? |
|
Definition
| The glow from a pea-size particle and the surrounding air as the particle burns up in our atmosphere |
|
|
