Foundations of Astronomy Ninth Edition Michael Seeds • The following slides are sample “clicker” questions for the new edition of Foundations of Astronomy. Thomson’s exclusive JoinIn on TurningPoint software lets you pose questions and display students’ answers seamlessly within your own PowerPoint lecture slides to enhance how your students interact with you, your lecture, and each other. • Contact your local Thomson representative to learn more. Or call us at 800-423-0563. ISBN: 0-495-10742-5 More on JoinIn: http://www.thomsonedu.com/support/index_joinin.html Which statement below best describes the motion of the moon relative to the stars? a. b. c. d. e. The moon moves Eastward relative to the stars about 1 degree per day. The moon moves Westward relative to the stars about 1 degree per day. The moon moves Eastward relative to the stars about 13 degrees per day. The moon moves Westward relative to the stars about 13 degrees per day. The moon does not move relative to the stars. 20% a 20% b 20% c 20% d 20% e How does the moon's motion relative to the stars compare to the sun's motion relative to the stars? a. b. c. d. e. The moon moves slower than the sun and in the same direction. The moon moves faster than the sun and in the same direction. The moon moves slower than the sun and in the opposite direction. The moon moves faster than the sun and in the opposite direction. The moon does not move relative to the stars. 20% a 20% b 20% c 20% d 20% e How does one cycle of the moon's motion relative to the stars compare to one cycle of the moon's motion relative to the sun? a. b. c. d. e. The two cycles take the same amount of time. The cycle relative to the stars is shorter than the cycle relative to the sun. The cycle relative to the stars is longer than the cycle relative to the sun. The two cycles vary in length such that at times the star cycle is shorter and at other times the sun cycle is shorter. The moon does not move relative to the sun. 20% a 20% b 20% c 20% d 20% e The time for one cycle of lunar phases is: a. b. c. d. e. about one day. about 24.8 hours. about one year. the same as the time for one cycle of the moon relative to the stars. the same as the time for one cycle of the moon relative to the sun. 20% a 20% b 20% c 20% d 20% e In one cycle of lunar phases, each crescent and gibbous phase has a duration of about one: 20% a. b. c. d. e. hour. day. week. month. year. a 20% b 20% c 20% d 20% e If the moon reaches full phase on May 6, it is at _____ phase on May 17. a. b. c. d. e. new waxing crescent waxing gibbous waning gibbous waning crescent 20% a 20% b 20% c 20% d 20% e The third quarter phase moon rises at about: a. b. c. d. e. sunrise. noon. sunset. midnight. There is no way to predict the time that a particular phase rises. 20% a 20% b 20% c 20% d 20% e Which of the following is true for an observer located at the tip of the umbra in this figure? 20% 20% 20% 20% 20% a. b. c. d. e. The angular size of the tack is greater than the angular size of the light source. The angular size of the tack is the same as the angular size of the light source. The angular size of the tack is less than the angular size of the light source. The distance to the tack is greater than the distance to the light source. The penumbra is darker than the umbra. What can be said about the maximum duration of lunar and solar eclipses? a. b. c. d. e. They both can last only a maximum of a few minutes. They both can last up to about six hours. A lunar eclipse can last up to 7.5 minutes and a solar eclipse up to almost six hours. A lunar eclipse can last up to almost six hours and a solar eclipse up to 7.5 minutes. It is impossible to make any prediction about the duration of eclipses. 20% a 20% b 20% c 20% d 20% e Of the six total lunar eclipses listed in this table, which two definitely cannot be observed by someone under clear skies located in Greenwich, England? a. b. c. d. e. Aug 28, 2007 & December 10, 2011 March 3, 2007 & December 21, 2010 February 21, 2008 & June 15, 2011 Sept. 7, 2006 & March 3, 2007 Dec. 21, 2010 & Feb. 21, 2008 20% a 20% 20% 20% b c d 20% e We can see total solar eclipses because: a. b. c. d. e. the linear diameters of the sun and the moon are almost equal. the distances to the sun and the moon are about the same. the angular diameters of the sun and the moon are almost equal. total solar eclipses would be visible on any planet with a moon. the moon always shows the same face to the Earth. 20% a 20% b 20% c 20% d 20% e We observe that the angular diameter of the moon is about the same as the angular diameter of the sun (about 1/2 degree). We also know that the AU is about 390 times the average Earth–moon distance. With this knowledge and this figure, what can we conclude about the linear diameters of the sun and moon? (Hint: you do not need the small-angle formula.) a. b. c. d. e. The linear diameter of the sun is the same as the linear diameter of the moon. The linear diameter of the sun is about 195 times the linear diameter of the moon. The linear diameter of the sun is about 390 times the linear diameter of the moon. The linear diameter of the sun is about 780 times the linear diameter of the moon. The linear diameter of the moon is about 195 times the linear diameter of the sun. 20% a 20% 20% 20% b c d 20% e Which of the following is true about the umbra of the moon's shadow? a. b. c. d. e. f. It is very dark, or a total shadow. It is semi-dark, or a partial shadow. Its "cone" points away from the sun. Its "cone" points toward the sun. Choices 1 and 3 above. Choices 2 and 4 above. 17% a 17% b 17% 17% c d 17% e 17% f During a total lunar eclipse, the moon is: a. b. c. d. e. f. completely dark. a reddish color. in Earth's umbra. in Earth's penumbra. Both 2 and 3 above. Both 1 and 3 above. 17% 1 17% 17% 17% 2 3 4 17% 5 17% 6 Which type of eclipse may be visible to all the people on one side of Earth? a. an annular eclipse b. a total solar eclipse c. a total lunar eclipse d. all of the above e. none of the above 20% a 20% b 20% c 20% d 20% e Using the small-angle formula, what is the angular diameter of Earth as seen from the moon? 25% a. b. c. d. 25% 25% 25% about 1.9 degrees; or 6850 seconds of arc about 1.0 degrees; or 3426 seconds of arc about 3.2 degrees; or 11520 seconds of arc about 10.1 degrees; or 36360 seconds of arc a b c d What part of the sun is visible during the "peak" of a total solar eclipse? a. b. c. d. photosphere chromosphere corona both 2 and 3 above e. all of the above 20% a 20% b 20% c 20% d 20% e Compare the range in angular size for the sun and moon shown in this figure. From these ranges we can conclude that: 20% a. b. c. d. e. Earth’s orbit around the sun and the moon’s orbit around Earth are both circular. Earth’s orbit around the sun is more elliptical than the moon’s orbit around Earth. Earth’s orbit around the sun is less elliptical than the moon’s orbit around Earth. We can not conclude anything about the orbits. Only one of the orbits is elliptical. 20% 20% 20% 20% a b c d e If the moon is at one of its nodes, it must be: a. at new phase. b. at first quarter phase. c. at full phase. d. at third quarter phase. e. on the ecliptic. 20% a 20% b 20% c 20% d 20% e A total lunar eclipse occurs when the moon is: a. b. c. d. at new phase. near the ecliptic. at full phase. both 1 and 2 above e. both 2 and 3 above 20% a 20% b 20% c 20% d 20% e A total solar eclipse occurs when the moon is: a. b. c. d. at new phase. near the ecliptic. at full phase. both 1 and 2 above e. both 2 and 3 above 20% a 20% b 20% c 20% d 20% e