Investigating Motions of the Sky

Transcription

1 Unit 1 Investigating Motions of the Sky Test Bank Questions 1. The length of an Earth day is determined by the time required for approximately one a. Earth rotation b. Earth revolution c. Earth orbit d. Sun rotation 2. At which location will the greatest altitude of the star Polaris be observed? a. Equator b. Tropic of Cancer c. North Pole d. All of the above, because it is the same everywhere 3. The apparent rising and setting of the sun is caused by a. Earth s rotation b. Earth s revolution c. Earth s orbit around the sun d. The sun s rotation 4. At which azimuth on the horizon does the sun appear to rise on July 4 in the United States? a. 90 b. North of 90 c. South of 90 d. Not enough information 5. If the sun is at the zenith, where on Earth might you be? (You may select more than one.) a. Equator b. Tropic of Cancer c. North Pole d. Houston, Texas (29 40 N W)

2 6. At which azimuth on the horizon does the sun appear to rise on an equinox in the United States? a. 90 b. North of 90 c. South of 90 d. Not enough information 7. Where in the sky can the planets be found? (You may select more than one.) a. along the ecliptic b. anywhere c. near the star Polaris d. on the celestial sphere 8. As observed from your current location, when will the sun be directly overhead at transit? (You may select more than one.) a. every day at noon b. on the equinoxes c. on the solstices d. never from current location 9. The positions of the planets in the sky on March 21: a. is different each year b. is the same each year c. repeats every four years d. is constantly changing 10. The daily path of the sun across the sky on March 21: a. is different each year b. is the same each year c. repeats every four years d. is constantly changing 11. What is the altitude of the zenith at 9:00 pm on March 21 at a latitude of 40 N? a. 0 b. 40 c. 50 d In the winter, the north pole of Earth s axis points toward the star Polaris. In the spring: a. The axis now points to another star, known as the North Star b. The axis now points to another star, Vega c. The axis still points toward the star Polaris d. The axis now points toward the sun

3 13. If a star s position at 8 pm is 120 azimuth and 35 altitude, its azimuth at 9 pm will be: a. Greater b. Less c. The same d. Not enough information 14. If the Earth s axis was NOT tilted at an angle, which of the following statements would be true? a. Summer would last much longer b. The winter would be much more severe c. There would be no seasons on Earth d. The polar ice caps would melt 15. The altitude of the sun at noon. a. varies by location on Earth b. is always 90 (directly overhead) c. is always between 23 and 67 d. never changes Short Answer Questions 1. Why are there different seasons on Earth? 2. Describe how the altitude of the sun varies over each of the four seasons. 3. How accurate is the statement: The sun always rises in the east and sets in the west? 4. Explain the characteristics of the solstices and equinoxes the Northern Hemisphere in terms of Earth s position in its orbit, relative distance from the sun, and Earth s tilt relative to the sun. 5. What causes constellations to be visible for only a number of months each year?

4 Unit Investigating the Sun Earth Moon 2 System Test Bank Questions 1. The rotation rate of the sun is about a. 25 days b. 24 hours c. 29 months d. it doesn t rotate at all 2. The rotation rate of Earth is a. 25 days b. 24 hours c. 29 days d. it doesn t rotate at all 3. The rotation rate of the moon is a. 30 or 31 days b. 24 hours c days d. it doesn t rotate at all 4. A neap tide is caused when. a. there is direct alignment of the sun-earth-moon b. another planet like Jupiter aligns with the sun c. the moon is at right angles in its orbit to the sun-earth line d. when Earth is at its closest approach to the sun 5. If the sun is the size of tennis ball (8 cm in diameter), Earth at the same scale is about cm in diameter. a. 1 cm b. 0.5 cm c. 0.1 cm d. too small to draw with a pencil

5 6. If the sun is the size of a tennis ball (8 cm in diameter), the distance of Earth from the sun at this scale is about a. 16 cm b. 80 cm c. 800 cm d. 80 meters e. 8 km 7. You would look for a slender crescent moon in the western sky a. any time after midnight b. just before sunrise c. during the early part of the evening d. some time between 11 p.m. and midnight 8. In which way does the moon move day by day in the sky, against the background of stars, when viewed from Earth? a. toward the north in summer and the south in winter b. toward the west c. in no particular direction and with no particular pattern d. toward the east 9. The cause of the moon s phases is a. the position of the moon relative to the sun and Earth b. clouds obscuring parts of the moon c. shadows of Earth covering parts of the moon d. the alignment of the moon with other planets in the solar system 10. When the moon is full: a. The angle between the sun and the moon is 180. b. The entire face of the moon is illuminated. c. The moon is halfway through its orbit d. All of the above 11. If you lived on the moon a. Earth would go through phases, from your point of view b. Earth would always appear full c. Earth would always appear half full d. Earth would seem to rise and set periodically 12. The new moon will always rise a. very close to sunrise b. very close to sunset c. at high noon d. at midnight

6 13. During a total solar eclipse a. the photosphere is obscured. b. the moon is new. c. the moon s umbra touches Earth. d. all of these e. none of these 14. In order for a lunar eclipse to occur, what must be true? a. The moon must be full b. The moon must be new c. The line of nodes must intersect the Earth-Sun plane d. both a. and c. e. both b. and c. 15. Earth doesn t experience an eclipse of the sun every month because a. sometimes the moon is too far away. b. the moon always keeps the same side toward Earth. c. the moon s orbit is not in the same plane as Earth s orbit. d. you have to be in the right place to see a solar eclipse. Short Answer Questions 1. What two major characteristics of the sun distinguishes it from both Earth and the moon? 2. Describe the motion (rising, setting, location) of a full moon over the course of one night. 3. Explain why the cycle of tides is stronger than normal during two periods of time each month and also weaker during other times. 4. Describe with a sketch why a particular total solar eclipse is not seen everywhere on Earth. 5. Why are solar and lunar eclipses such rare events?

7 Unit 3 Investigating Planets Text Bank Questions 1. The overall shape of the orbits of most of the planets in our solar system is: a. elliptical b. parabolic c. slightly elliptical, nearly circular d. perfectly circular 2. Which planet has not yet been visited by a human spaceflight mission? a. Mercury b. Jupiter c. Mars d. Venus e. More than one of the above f. None of the above 3. Compared to the Jovian planets, on average, the terrestrial planets are: a. smaller and more massive b. smaller and less massive c. larger and more massive d. larger and less massive 4. Which planet is the largest in the solar system? a. Mars b. Neptune c. Saturn d. Jupiter e. Uranus 5. Which of the following is not a characteristic that must be explained by a model of how the solar system formed? a. the planets orbits lie pretty much in the same plane b. the planets revolve around the sun in the same direction c. all the planets and the sun revolve around the galaxy d. the planets orbits are pretty much circular

8 6. The atmospheres of Venus and Mars are composed primarily of: a. hydrogen and helium b. carbon dioxide c. methane d. ammonia 7. Both Earth s moon and Mercury have very large temperature variations between day and night. The main reason for this large variation is: a. small mass b. rocky composition c. distance from the sun d. lack of atmosphere e. lack of surface water 8. A planet s surface gravitational force is related to: (Mark all that apply.) a. the radius of the planet b. the amount of atmosphere on the planet c. the mass of the planet d. the distance between the planet and the sun 9. How is it possible that Venus s surface temperatures can be hotter than Mercury s? a. Venus is closer to the sun. b. Venus s larger size means that is absorbs more heat. c. Venus s lack of atmosphere allows sunlight to hit the surface without reflection. d. Venus has quite a lot of carbon dioxide in its atmosphere. 10. Which of these are characteristics of the Jovian planets? a. large size b. composed mostly of gases and ices c. located beyond the orbit of Mars d. have very few moons e. water vapor is present 11. Which of the following are planetary characteristics important to habitability? (Mark all that apply.) a. Water b. Temperature c. Diameter d. Atmosphere e. Orbital period

9 12. On the surface of Venus, small craters are: a. very common in the highland areas b. rare because of the very thick atmosphere c. rare because they ve been filled in by water erosion d. common throughout the surface 13. The composition of Earth s atmosphere is: a. 95% carbon dioxide, some water vapor b. 77% nitrogen, 21% oxygen c. 77% nitrogen, 21% carbon dioxide d. nitrogen, oxygen, carbon dioxide, and water vapor in about equal amounts 14. Kepler s third law explains that, among the planets in our solar system, the farther a planet is from the sun, then the: a. more eccentric is its orbit b. slower its orbital speed c. faster its orbital speed d. more inclined is its orbit 15. Which of the following statements is true about space exploration (as of 2010)? a. Astronauts have landed on three planets with our solar system b. Astronauts have exited our solar system c. Astronauts have never gone to solar system bodies other than Earth and its moon d. Astronauts have visited only Mars Short Answer Questions 1. Explain the factors that make astronauts weight vary depending on which planet or moon they are standing on. 2. The force of gravity exerted between the sun and every other object in the solar system varies by the inverse square of the distance between them. Explain what this means quantitatively using the distances of the Earth (1 AU) and Neptune (20 AUs) in your explanation. 3. Summarize the importance of Kepler s Laws in determining the nature of the orbits of planets around the sun. 4. Describe the two most likely places in the solar system that might harbor single-celled life, or may have had life exist there in the past. Justify your choices. 5. Describe the principal differences between terrestrial and Jovian planets.

10 Unit Investigating 4 Tools of Astronomy Test Bank Questions 1. Which color of light carries the most energy? a. Red. b. Yellow. c. Green. d. Blue. e. All visible light has the same energy. 2. Which of the following types of electromagnetic radiation has the shortest wavelength? a. Ultraviolet. b. Visible light. c. X-rays. d. Radio. e. Infrared. 3. Which of the following characteristic(s) of distant objects can be discovered by analyzing electromagnetic radiation? a. temperature. b. color. c. chemical composition. d. all of the above. e. none of the above. 4. If the light coming from a distant object produces a bright emission-line spectrum, which of the following best describes the physical conditions of that object? a. Hot and dense. b. Cool and dense. c. Hot and diffuse. d. Cool and diffuse. 10

11 5. A CCD does NOT: a. count photons. b. contain a grid of silicon pixels. c. record color information. d. store charged particles. 6. When creating an image of an astronomical object, the choice of a color palette: a. changes the data. b. helps emphasize certain features and subtle details. c. provides a way of visualizing forms of electromagnetic radiation other than visible light. d. both a. and b. e. both b. and c. 8. Why are some telescopes placed in space? a. Telescopes in space are able to get significantly closer to astronomical objects. b. Some types of electromagnetic radiation cannot penetrate Earth s atmosphere. c. Space telescopes are less expensive than ground telescopes. d. There is no gravity in space, so bigger, heavier mirrors or lenses can be used. 9. What does a filter do? a. reflects a specific range of wavelengths. b. changes the wavelength of the light passing through it. c. transmits a specific range of wavelengths. 10. What type of instrument is used to determine the chemical composition of an object? a. telescope. b. CCD c. spectroscope. d. broad-band filter. 11. The color of a star is most directly related to its. a. mass b. temperature c. density d. luminosity e. distance from Earth 12. To determine the composition of the sun, astronomers study. a. a series of visible-light images b. the sun s emission line spectrum c. the sun s absorption line spectrum d. the sun s continuous spectrum e. images of the sun made from several types of electromagnetic radiation 11

12 13. Which of the following lists of electromagnetic radiation types is in the correct order from shortest wavelength to longest? a. visible light, radio waves, ultraviolet waves, x rays, infrared waves b. radio waves, infrared waves, visible light, ultraviolet waves, x rays c. x rays, ultraviolet waves, visible light, infrared waves, radio waves 14. True or False: All forms of electromagnetic radiation travel at the same speed. 15. Telescopes help us see distant objects by. a. collecting and focusing light with mirrors or lenses b. using narrow piping to gather and redirect light towards a gas tube c. using sophisticated mechanics to move the objects closer to us Short Answer Questions 1. Why do astronomers rely so heavily on electromagnetic radiation when studying astronomical objects? 2. What advantages do CCDs have over observations with the human eye? 3. How do the different bands of the electromagnetic spectrum differ from each other? What characteristic is the same among them? 4. How does an emission spectrum of an element differ from its absorption spectrum as seen in a star? 5. How do astronomers determine an object s color and temperature? 12

13 Unit 5 Investigating Stars Test Bank Questions 1. The quantity that determines where a star will be (or was) on the main sequence is a. the age of the star b. the composition of the star c. the distance to the star d. the initial mass of the star 2. A Hertzsprung-Russell diagram reveals the lives of stars because it shows stars that. a. all have the same age b. all have the same mass c. all have the same chemical composition d. are at different stages of their lives 3. The reactions that produce the energy of stars are a. chemical reactions b. fusion reactions c. fission reactions d. reactions unknown on Earth 4. The heaviest element produced by stellar fusion is a. iron b. uranium c. carbon d. oxygen e. einsteinium f. lockwoodium 5. On the main sequence, hot stars are generally than cool ones. a. more massive and longer-lived b. less massive and longer-lived c. more massive and shorter-lived d. less massive and longer-lived e. more massive, but we don t know how long they live 13

14 6. On the H-R diagram, stars with the smallest diameters are found. a. at the upper left end of the main sequence b. at the lower right end of the main sequence c. in the upper right corner of the H-R diagram d. in the upper left corner of the H-R diagram 7. Which of the following star types are the most numerous in a large sample of stars? a. red dwarfs b. white dwarfs c. red giants d. black holes e. white giants 8. A GIII star is. a. a star quite like our sun b. a white main-sequence star c. a yellow giant star d. a red supergiant star e. a white dwarf star 9. The brightness of a star in the night sky, by itself, a good indicator of. a. its distance from Earth b. its temperature c. its color d. its absolute magnitude e. nothing 10. The color of a star is most directly related to its. a. mass b. temperature c. density d. luminosity e. distance from Earth 11. The lifetime of a star will be very short if the initial mass of the star is. a. about equal to our sun s b. less than that of the sun c. much greater than that of our sun d. about twice the mass of the sun 14

15 12. When a one solar mass star evolves to a red giant stage. a. the core gets hotter and the surface getters hotter b. the core gets hotter and the surface gets cooler c. the core gets cooler and the surface gets hotter d. the core gets cooler and the surface gets cooler e. astronomers have no idea what really happens 13. When a massive star dies, the end result is that it. a. becomes a neutron star b. becomes a black hole c. blows itself into atoms, leaving nothing behind d. could be any of the above outcomes 14. A planetary nebula is a. a planet very far away b. a place where stars are born c. a stage late in the life of most stars d. a cloud of gas with a hot, central star in the center e. both c and d 15. What supports the mass of a neutron star? a. electron degeneracy b. neutron degeneracy c. nothing can support its mass d. gravitational repulsion e. magnetic forces 16. Which of the following stars have no active nuclear reaction occurring within them? a. white dwarfs b. red giants c. main sequence stars d. T Tauri stars e. stars like our sun 17. When a cool, main-sequence star has exhausted its nuclear fuel, it will become. a. a red giant star b. a white dwarf star c. a variable star d. a neutron star e. a black hole 15

16 18. Where can you find an example of a pulsar? a. in the center of the galaxy b. in the Crab nebula c. in the center of the sun d. in the Orion nebula e. pulsars are a theoretical construct 19. Which of the following statements is true about supernovae? a. supernovae are the only source of neutrons in the universe b. supernovae compress gas in nearby gas clouds so that new stars can form c. elements heavier than iron are produced chiefly in supernovae explosions d. supernovae are the major source of light in most galaxies e. a and c f. b and c g. b and d 20. A black hole is a. an object of zero volume and infinite density b. an object from which nothing, not even light, can escape c. an object that emits x rays as matter falls into it d. an object that disappears from our universe e. all of the above Short Answer Questions 1. Describe the process of nuclear fusion in stars. 2. Sketch an H-R diagram. Circle areas that you might find: a. white dwarf stars b. main sequence white stars c. yellow giant stars d. red supergiant stars e. Cepheid variable stars f. red dwarf stars g. brown dwarf stars 3. How is the temperature of a star related to its color? Its mass? 4. What are three significant differences between the evolutionary stages of low- and high-mass stars? 5. What happens inside the core of a star the moment before a supernova explosion? What are the three possible outcomes or objects produced of this event? 16

17 Unit 6 Investigating the Universe Test Bank Questions 1. A typical distance between star systems in the disk of the Milky Way is. a. a few light years b. a trillion miles c. a billion miles d. a million miles 2. Which of the following is not a piece of evidence in favor of the big bang theory? a. the discovery of heavier elements in the oldest stars b. the background radiation c. the abundance of helium in the universe d. the expansion of the galaxies 3. The reason for the expansion of the universe is explained by a. the big bang theory b. the steady state theory c. theory of relativity d. Hubble s law 4. According to the big bang theory about how old is the universe? a. about 100 million years b. about 13 billion years c. about 500 billion years d. the big bang theory does not predict the age of the universe 5. The best method of determining the distance to a relatively near galaxy is. a. a bright Cepheid variable b. novae c. bright emission nebulae d. none of the above 17

18 6. Star a has a parallax twice that of star b. What can you say about the relative distances of the two stars? a. star a is twice as far away as star b. b. star b is twice as far away as star a. c. you cannot tell anything about their relative distances without knowing the actual parallaxes d. you cannot tell anything about their relative distances because parallax is related to motion and not to distance 7. According to Hubble s law more rapidly moving galaxies are now. a. farther away from us b. closer to us c. accelerating rapidly d. already contracting toward another big bang 8. When we see the Milky Way in the sky, we are looking at. a. the center of our galaxy b. stars in the plane of the galaxy c. companion galaxies to our own d. the combined light of distant galaxies 9. Which of the following types of galaxies have a small mass and are shaped like footballs? a. supergiant ellipticals b. dwarf ellipticals c. spirals d. irregulars 10. Which of the following are examples of the term standard candle? a. Cepheid variables b. the brightest galaxy in a cluster c. supernovae d. all of the above 11. The use of supernovae as standard candles for determining distance assumes that. a. all supernovae have the same actual brightness b. all supernovae occur in galaxies c. all galaxies are moving away from us d. supernovae explosions occur in Cepheid variable stars 18

19 12. In order to plot a graph of Hubble s law, we need to know what information about galaxies? a. distances and red shifts b. luminosities and red shifts c. diameters and red shifts d. shapes and red shifts e. colors and red shifts 13. In the universe as a whole, the effect of gravity is. a. to try to pull everything together b. to try to push everything apart c. so random that no net effect is present d. negligible because of the immense distances involved 14. In general, most galaxies fall into categories based on their shape and structure. a. 3 b. 5 c. 10 d. There is only one type of galaxy 15. The elements, which formed after the big bang explosion, were. a. destroyed in later generations of stars b. predominantly light elements like hydrogen and helium c. mostly heavy elements like iron and lead d. mostly heavy elements which were later broken down into light elements Short Answer Questions 1. Describe in one paragraph the basic story of how our universe came to exist. 2. Explain why a ladder is used as a metaphor for how astronomers measure distances in the universe. 3. Draw a diagram and use words to explain how you can measure the distance to nearby stars using the parallax method. 4. Explain how Cepheid variable stars have predictable luminosities and how that information is used to help us measure distances to nearby galaxies. 5. Explain how Hubble s Law can be used to measure the distance to even the most distant observable objects in the universe. 6. What is the relationship between the distance of an object and the speed at which it moves away from us? What is the origin of that relationship? 19