Online Midterm
Assignment 2
1. The sun and stars rise and set because of the Earth’s [rotation, revolution]
2. The sun moves about how many degrees per day along the ecliptic?
3. True or False: Astrology is considered an important branch of astronomy.
4. On February 1 what constellation will the sun appear to be in?
Capricornus
5. The zodiac is how many degrees wide?
6. As seen from the north celestial pole all the planets revolve [clockwise, counterclockwise].
7. Why do we always find the planets near the ecliptic?
8. What is the angle between the celestial equator and the ecliptic?
9. On about what date does the sun cross the celestial equator heading to the south?
10. The Earth is nearest the sun around the [first part of July, first part of January].
11. The sun is furthest north of the celestial equator at the time of the [summer, winter] solstice.
12. Which planet can appear at a greater angular distance from the sun, Mercury or Venus?
13. The moon moves [eastward, westward] against the background of the stars.
14. When the moon is between new and first quarter it is [waxing crescent, waxing gibbous].
15. The first quarter moon rises at about what time?
16. The actual time it takes the moon to revolve around the Earth is [27.3, 29.5] days.
17. True or False: The moon always keeps the same side facing Earth because the moon does not rotate.
18. The moon’s orbit around the Earth is tilted by about how many degrees to the plane of the Earth’s orbit around the sun?
19. To have a lunar eclipse, the moon must be [new, full].
20. Why can the totally eclipsed moon look reddish?
21. To see a total solar eclipse you must be in the [umbra, penumbra] of the moon’s shadow.
22. What is the maximum time the sun can remain totally eclipsed?
23 To have an annular eclipse the moon must be at or near [apogee, perigee].
24. When the sun is partially eclipsed, what is a safe way to view it?
25. The sun’s outer atmosphere is called the [corona, photosphere].
26. What causes the diamond-ring effect?
27. What is the Milankovitch hypothesis? [Give a brief description]
28. Aristotle believed in the [heliocentric, geocentric] theory.
29. How did Ptolemy explain retrograde motion?
30. How did Copernicus explain retrograde motion?
31. Who supplied the observational data that enabled Kepler to come up with his three laws of planetary motion?
32. True or False: The planets revolve around the sun in ellipses with the sun at the geometric center of the ellipse.
33. Suppose a planet sweeps out an area, call it A, in one day. In terms of A, Kepler’s second law tells us it would sweep out how large an area in five days?
34. If a planet had an average distance from the sun of 4 AU, how long does it take to revolve around the sun? [Hint: Use Kepler’s third law]
35. How did Galileo’s discovery of 4 moons of Jupiter help support the heliocentric theory?
36. In the Ptolemaic theory, could we ever see Venus in the gibbous phase?
37. Why was Galileo put on trial? [Be brief]
38. Suppose object A exerts 8 pounds of force on object B. How much force does B exert on A? [Hint: use Newton’s third law.
39. True or False: Mass and weight are the same things.
40. If two objects are moved 4 times further apart, their gravitational attraction will be how many times weaker?
41. True or False: Astronauts orbiting Earth feel weightless because they are beyond Earth’s gravity.
42. A geosynchronous satellite is how many miles from the Earth’s center?
43. The center of mass of the Earth and moon lies closer to the [moon, Earth].
44. The circular velocity just above the Earth’s atmosphere is how many miles per hour?
45. At new and full moon we have [neap, spring] tides.