Download TOPIC 14 – MOTIONS OF EARTH, MOON, SUN

TOPIC 4 – MOTIONS OF EARTH, MOON, SUN
Apparent Motions of Celestial Objects – stars, sun, moon, and planets
1. What is an apparent motion?__________________________________
2. What is causing the apparent motion of stars moving across the sky from
east to west? ______________________________________________
Daily Motion of Stars
3. How do most celestial (heavenly) objects appear to move across the sky?
_________________________________________________________
4. How do some of the stars near the North Star or Polaris appear to move?
_________________________________________________________
5. What is an arc? __________________________________________
6. What is the constant rate of all DAILY (24 hour period) motion of
celestial objects? ___________________________________________
Apparent Motion of the Planets
7. Due to the complicated motion of Earth and the other planets revolving
around the sun in different orbits and at different speeds, when the planets
are viewed from earth what do the appear to do? ____________________
_________________________________________________________
Apparent Motions of Earth’s Moon
8. Does the moon follow the daily east-to-west motion of the stars? _____
9. How many minutes does the moon appear to rise later each day? _______
Apparent Motions of the Sun
10. What shape is the sun’s apparent path? ________________________
11. What are the changes in sun’s path with the seasons? ______________
_________________________________________________________
12. What happens to the number of daylight hours as the length of the sun’s
path increases? What season has the greatest number of daylight hours?
_________________________________________________________
13. Where does the sun rise and set in the spring and fall? _____________
_________________________________________________________
14. Where does the sun rise and set in the summer? _________________
15. Where does the sun rise and set in the winter? __________________
Changes in the altitude of the sun at noon
Altitude – the angle in degrees of a celestial object above the horizon
16. What time of day does the sun reach the highest position in the sky? __
_________________________________________________________
17. What 2 factors determine the altitude of the sun at noon?__________
_________________________________________________________
18. Between what 2 latitudes is the sun directly overhead (90°) at noon?
_______________________________________________________
19. Is the sun ever directly overhead anywhere in the continental U.S.? ___
20. According to Figure 4-4, at what latitude is the sun directly overhead on
September 23 (Fall Equinox) and March 23 (Spring Equinox)? ___________
21. The Sun is directly overhead at the Tropic of Cancer (23.5°N) on what
date (Summer Solstice)? ______________________________________
22. The Sun is directly overhead at the Tropic of Capricorn (23.5°S) on
what date (Winter Solstice)? __________________________________
MODELS THAT HELP EXPLAIN APPARENT CELESTIAL MOTIONS
Geocentric Models
23. Most early cultures believed in the geocentric model. What is the
geocentric model? ___________________________________________
24. What is a heliocentric model? _______________________________
25. What 2 motions of earth are explained in a heliocentric model? ______
_________________________________________________________
ACTUAL EARTH MOTIONS
Rotation of Earth
26. What is earth’s rotation?___________________________________
27. What is its axis? _________________________________________
28. How many degrees is earth’s axis tilted from a line perpendicular to the
plane of its orbit? Does the tilt ever change? _______________________
29. The north end of the axis is directly below what star? _____________
30. How long does it take earth to rotate 360° from WEST TO EAST?___
Evidence of Earth’s Rotation
Hard to prove rotation before satellites because we cannot feel it
The Foucault Pendulum
31. When a Foucault pendulum was observed in 1851, how did it appear to
change? __________________________________________________
32. How is this proof of rotation? _______________________________
_________________________________________________________
DIGGING DEEPER
33. The path of the Foucault pendulum only appears to change. What is
actually happening? __________________________________________
_________________________________________________________
The Coriolis Effect
34. What is the Coriolis Effect? ________________________________
_________________________________________________________
35. In the Northern Hemisphere, which direction is the deflection? ______
36. In the Southern Hemisphere, which direction is the deflection? ______
37. Why does this deflection occur? _____________________________
38. What are some examples of matter deflected with respect to Earth’s
surface? __________________________________________________
Evidence of Earth’s Revolution Around the Sun
39. How long does it take the Earth to revolve around the sun? _________
40. Earth’s orbit is a slightly eccentric ellipse. Eccentricity means the
degree of ovalness of an ellipse or how far it is from being a circle. Does our
slightly elliptical orbit cause the seasons? _________________________
41. Seasonal changes are evidence for revolution because as earth travels in
its orbit around the sun due to earth’s tilt different parts of earth receive
the direct rays of the sun.
42. If the same part of Earth received the more direct rays of the sun,
would the seasons change? _____________________________________
43. What is a constellation? ___________________________________
44. Why are having different constellations associated with each of the 4
season’s proof of revolution? ___________________________________
45. What happens to the sun’s apparent diameter as Earth revolves in its
slightly elliptical orbit? (this happens because of the changing distance from
the sun) __________________________________________________
Earth and Moon Motions and Time
46. What is the concept of the month based on? ____________________
47. What is a day based on? ___________________________________
48. What is a year based on? __________________________________
Local Time
49. What is time based on? ____________________________________
50. What is true about time at all locations on the same north-south line,
meridians of longitude? _______________________________________
Time Zone or Standard Time
51. How many time zones are there? _____________________________
52. How wide apart and what is the difference in time between time zones?
_________________________________________________________
Actual Motions of Earth’s Moon
53. What common events are the results of the revolution of the moon
around Earth as Earth revolves around the sun? _____________________
54. What is the tilt and period of the moon’s revolution?
_________________________________________________________
Moon Phases
55. Except during lunar eclipses, how much of the moon is always receiving
light from the sun? __________________________________________
56. Why does an observer on Earth see varying amounts of this lighted half
as the moon moves in its orbit? _________________________________
57. What are the moon’s phases? _______________________________
_________________________________________________________
58. What type of change are the phases of the moon? ________________
59. The period from one full moon to the next is how many days? ________
60. Moon’s period of revolution is only how many days? ________________
(As the moon revolves around Earth, Earth is moving in its orbit around
the sun. Therefore, it takes longer (approximately 2 days) for the moon
to complete its full cycle from full moon to full moon)
Tides
61. What causes the tides? ____________________________________
_________________________________________________________
_________________________________________________________
62. The tidal effect is caused primarily by what? ____________________
63. Why? _________________________________________________
64. Few ocean shores experience an ideal cycle of tides but normally how
many high tides and low tides are there in a 24 hour cycle? _____________
65. When the moon, earth and sun are in a straight line you get higher high
tides and lower low tides. What is the result? ______________________
66. When the moon is a quarter phase, the sun is at a 90° angle to moon’s
force resulting in lower high tides and higher low tides. What is the result?
_________________________________________________________
Eclipses
67. What is an eclipse? _______________________________________
_________________________________________________________
Lunar Eclipse
68. What is a lunar eclipse? ___________________________________
69. This ONLY happens during what moon phase? ___________________
70. Why doesn’t this happen every month? ________________________
_________________________________________________________
Solar Eclipse
71. What is a solar eclipse and during what moon phase can it happen? ____
_________________________________________________________