1. Unit 3 The Earth – Moon – Sun System
Vocabulary
Review

2. the periodic rise and fall of the water levels in the oceans and other large bodies of water
tide

3. the time required for Earth to rotate once on its axis
day

4. a tide of increased range that occurs two times a month, at the new and full moons
spring tide

5. the time required for Earth to orbit once around the sun
year

6. the point at which the sun is as far north or as far south of the equator as possible; the area of sunlight is at maximum in one hemisphere and at minimum in the other
solstice

7. the outer part of a shadow such as the shadow cast by the Earth or moon in sunlight is only partially blocked
penumbra

8. the force of attraction between two objects that is due to their masses
gravity

9. the motion of a body that travels around another body in space; one complete trip along an orbit
revolution

10. a natural or artificial body that revolves around a celestial body that is greater in mass
satellite

11. a tide of minimum range that occurs during the first and third quarters of the moon
neap tide

12. the moment when the sun appears to cross the celestial equator; sunlight shines equally on the northern and southern hemispheres
equinox

13. the difference in levels of ocean water at high and low tides
tidal range

14. an event in which the shadow of one celestial body falls on another
eclipse

15. the different appearances of the of the moon from Earth throughout the month
lunar phase

16. a division of the year that is characterized b recurring weather conditions and determined by both Earth’s tilt relative to the sun Earth’s position in its orbit around the sun
season

17. a shadow that blocks sunlight; such as the conical section in the shadow of Earth or the moon
umbra

18. the spin of a body on its axis
rotation