Unit 4 Vocabulary

12345678910111213141516
Across
  1. 5. a circle on the surface of a sphere that is the curve of intersection of the sphere with a plane passing through its center
  2. 6. the time interval in which the phases repeat for example from full to full phase
  3. 9. Earth’s rotation period as defined by the position of the Sun in the sky; the time between successive passages of the Sun through the meridian
  4. 10. the angular distance north or south of the celestial equator
  5. 13. the coordinate for measuring the east-west positions of celestial bodies; the angle measured eastward along the celestial equator from the vernal equinox to the hour circle passing through a body
  6. 14. when a body rotates at the same rate that it revolves around another body, for example the moon
  7. 15. an arbitrary line on the surface of Earth near longitude 180° across which the date changes by one day
Down
  1. 1. an eclipse of the Sun by the Moon, caused by the passage of the Moon in front of the Sun
  2. 2. the period of the Moon’s revolution about Earth measured with respect to the stars
  3. 3. a great circle on the terrestrial or celestial sphere that passes through the poles
  4. 4. time based on the rotation of Earth
  5. 7. time as measured by the position of the Sun in the sky, for example this would be the time that would be indicated by a sundial
  6. 8. the different appearance of light and dark on the Moon as seen from Earth during its monthly cycle, from new moon to full moon and back to new moon
  7. 11. an eclipse of the Moon, in which the Moon moves into the shadow of Earth
  8. 12. Earth’s rotation period as defined by the positions of the stars in the sky; the time between successive passages of the same star through the meridian
  9. 16. alternate rising and falling of sea level caused by the difference in the strength of the Moon’s gravitational pull on different parts of Earth