1 Astronomy 1010 Planetary Astronomy Sample Questions for Exam 1 Chapter 1 1. A scientific hypothesis is a) a wild, baseless guess about how something works. b) a collection of ideas that seems to explain a phenomenon. c) an absolutely unbreakable law of physics. d) a first guess about what causes a physical phenomenon. 2. Astronomers study a) the planets of the solar system. b) the sun. c) stars and nebulae. d) galaxies and large scale structures in the universe. e) All of the above. 3. In science, the final arbiter on whether a theory is correct is a) a committee of distinguished scientists. b) the Nobel committee in Stockholm Sweden. c) Nature. d) the scientist most responsible for developing the theory. 4. The number , written in scientific notation, is a) 2.5x10-11 b) 25x10-11 c) 2.5x10 11 d) 25x The language of science is a) Greek. b) Latin. c) mathematics. d) English. e) None of the above, science has no language. 6. The light travel time to the nearest star other than the Sun is measured in a) seconds. b) hours. c) days. d) years. e) None of the above, light travels instantaneously.
2 7. Almost all the atoms in your body a) are primordial and have existed since the beginning of time. b) were created in the cores of stars that died billions of years ago. c) were created in our sun. d) were created in the center of the Earth and brought to the surface by volcanoes. 8. The science of astronomy began with a) observations of the patterns of the stars at the beginning of recorded history. b) the construction of the first telescope in the 1600 s. c) the Greek astronomer Ptolemy. d) ancient Babylonians. 9. The Cosmological Principle is a) There is nothing special or unique about the Earth. b) Observers on the Earth are special and only we see the universe as it really is. c) Observers on the Earth see a different universe than observers in other galaxies. d) The Universe is infinite. 10. The scientific method is a) a specific set of experiments scientists perform to determine the truth of their theory. b) a series of steps scientists use to try and explain phenomena in nature. c) the method scientists use to form an hypothesis. d) the method scientists use to analyze their experimental data. Short Answer Questions 1. Describe what is meant by light travel time. Give the light travel time to a number of celestial objects and discuss how it relates to their distance from Earth. 2. Describe the scientific method and how scientists use it to explain physical phenomena. 3. Why is it that most astronomers believe we are living in the Age of Exploration for astronomy? What are some of the explorations that have taken place in the last 50 years?
3 Chapter 2 1. The 88 official constellations used today can be traced to a) every ancient culture around the world. b) European culture from 2000 years ago for northern constellations and 500 years ago for southern ones. c) ancient Chinese culture for the northern constellations and Australian aboriginal culture for southern ones. d) North American Indian culture for northern constellations and ancient South America cultures for southern ones. 2. The daily motions observed in the sky are due to a) the rotation of the Earth about its polar axis. b) the rotation of the celestial sphere about the celestial poles. c) the orbit of the Earth around the sun. d) the motion of the sun around the center of the Milky Way. 3. We see different constellations during the different seasons a) because the stars are continually dying and new stars are being born. b) because the celestial sphere slowly rotates around the Earth. c) because the Earth orbits around the sun and we can only see the constellations that are on the opposite side from the sun. d) because of the rotation of the Earth about its polar axis. 4. If you are floating in space directly above the North Pole of the Earth, you will see Earth a) rotate clockwise around the North Pole. b) rotate counterclockwise around the North Pole. c) remain fixed in space. 5. The celestial equator is a) the path the Sun follows around the celestial sphere. b) the projection of the plane of the Earth s equator onto the celestial sphere. c) the projection of the line connecting the poles of the Earth onto the celestial sphere. d) the circle around the celestial sphere formed by the Milky Way. 6. The celestial poles are a) the path the Sun follows around the celestial sphere. b) the projection of the line connecting the poles of the Earth onto the celestial sphere. c) the projection of the plane of the Earth s equator onto the celestial sphere. d) the circle around the celestial sphere formed by the Milky Way.
4 7. Circumpolar constellations are constellations that a) rise in the east an set in the west daily. b) never set, just circle the celestial pole. c) rise in the west and set in the east daily. d) rise in the south and set in the north annually. 8. The principle cause of the seasons on Earth is a) the 23.5 tilt of the Earth s rotation axis. b) the change in distance between the Earth and the Sun due to the elliptical orbit of the Earth. c) the change in the tilt angle of the Earth s rotation axis as it orbits the Sun. d) the increase and decrease in the heat output of the Sun during the year. 9. The AU is defined as a) the average distance to the nearest star. b) the average distance between the Earth and the Sun. c) the distance light travels in one year. d) the average diameter of the planet Earth. 10. The two times when the Sun crosses the celestial equator are a) the winter and summer solstices. b) during the full and new Moon. c) around January 1 and July 1. d) the spring and fall equinoxes. e) None of the above, the Sun never crosses the celestial equator. 11. The precession of the equinoxes is a) the slow movement of the celestial pole over thousands of years due to the precessional wobble of the Earth. b) the slow changing of the patterns of the stars due to their actual motion with respect to the Sun. c) the motion of the Sun through the Milky Way over billions of years. d) the seasonal changing of the visible constellations due to the Earth orbiting the Sun. 12. At noon on the summer solstice in the northern hemisphere, the Sun is directly over a) the North Pole. b) the Equator. c) the Tropic of Cancer. d) your head where ever you are.
5 13. The calendar currently in use is a) based on 365 days in every year. b) the Gregorian calendar with 365 days in most years, 366 days in years evenly divisible by four except century years and 366 days in century years evenly divisible by 400. c) the Julian calendar with 366 days in most years and 365 days in all years evenly divisible by four. d) the Julian calendar with 365 days in most years and 366 days in all years evenly divisible by four. 14. The Moon goes through phases because a) the Earth blocks the light from the Sun so only part of the moon is lit. b) the Moon orbits the Earth so that we only see part of the lit face as it goes around us. c) the Earth orbits the Moon so that we only see part of the lit face as we go around it. d) the Sun orbits the Earth and Moon so that only part of the Moon is lit at any time. 15. The rotational period of the Moon is a) the same as the orbital period. b) longer than the orbital period. c) shorter than the orbital period. d) zero, the Moon does not rotate at all 16. If more than half but less than all of the Moon is visible it is called a) a Full Moon. b) a crescent Moon. c) a gibbous Moon. d) a New Moon. 17. If the amount of the Moon that is visible is increasing it is a) a waning Moon. b) a waxing Moon. c) a Full moon. d) None of the above, all of the Moon is always visible. 18. A lunar eclipse occurs a) when the Moon comes between the Earth and the Sun. b) when the Earth comes between the Moon and the Sun. c) when the Sun comes between the Earth and the Moon. d) every month during the Full Moon.
6 19. Total solar eclipses are rare events because a) the Sun is so much farther away than the Moon it appears much larger than the Moon. b) the Moon is so much closer than the Sun it appears much smaller than the Sun. c) the distance to the Moon is the same as the distance to the Sun. d) the alignment between the Sun and the moon must be very precise since they both appear to be the same angular size. Short Answer Questions 1. Describe the origins of the constellations and their modern day definition. 2. Using the celestial sphere model, describe motions of the stars. Be sure to make reference to the important reference marks of the celestial sphere. 3. Briefly describe the causes of the seasons and how they are related to the apparent motion of the sun along the ecliptic and the position of the earth in its orbit around the sun. Make specific reference to the earth s perihelion and aphelion and their relationship to the seasons. Include mention of the four important dates in the seasonal motion of the sun. 4. Describe a complete lunar cycle beginning and ending with the new moon. Use a diagram to illustrate the relationship between the sun, moon and earth during each phase 5. Using a diagram and a few words describe a total lunar eclipse. 6. Using a diagram and a few words describe a total solar eclipse. Chapter 3 1. Ptolemy s model of the solar system had the planets a) moving in perfect circles centered exactly on the earth. b) fixed in space and never moving. c) moving around the sun in circular orbits. d) moving on epicycles which moved along the deferent whose center was offset from the earth by the eccentric. 2. Copernicus proposed that a) the Earth was at the center of the solar system. b) the Sun was at the center of the solar system. c) there was no center to the solar system. 3. Tycho Brahe is best known for a) his close cooperation and friendship with Johannes Kepler. b) his invention of the telescope. c) his continuous, detailed and accurate observations of the planets and stars. d) his theoretical model of the universe.
7 4. Which of the following is not one of Kepler s laws of planetary motion? a) the Sun is at the center of the universe. b) the square of a planets orbital period is proportional to the cube of the planets average distance from the Sun. c) the planets move on ellipses with the Sun located at one focus. d) a line drawn from a planet to the Sun will sweep out equal areas in equal time periods. 5. In addition to his astronomical observations, Galileo Galilei is known for a) his close cooperation with and strong support for the Roman Catholic Church. b) his development of new physics to replace the old incorrect physics of Aristotle. c) his invention of the reflecting telescope. d) his close friendship and cooperation with Tycho Brahe. 6. Which of the following is not one of Newton s three laws of motion? a) For every force there is an equal and opposite reaction force. b) A line drawn from a planet to the Sun will sweep out equal areas in equal time periods. c) The rate of change in the velocity of a body is directly proportional to the net force on the body and inversely proportional to the mass of the body. d) A body at rest or in motion at constant velocity will remain in that state unless acted on by some net external force. 7. According to Newton s 1 st law of motion a) the planets move in circular orbits with the sun located at the center of the circle. b) if an object is moving in a straight line at a constant speed it will continue to do so unless some outside force acts on it. c) the more massive an object is the larger the acceleration it will experience for the same force. d) objects move to their natural place when left to themselves. Short Answer Questions 1. State Kepler s Laws of Planetary Motion and the consequences and meaning of those laws. 2. Describe an ellipse. Include a diagram with the major parts of the ellipse labeled and defined. 3. State Newton s Three Laws of motion. Give examples of each of the laws. 4. Describe some of Galileo s contributions to physics and astronomy and why they led to problems with the Catholic Church.