Moon Unit Crossword

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Across
  1. 1. This layer of the Moon is actually much thinner on the side that faces the Earth than on the far side.
  2. 7. This theory of the origin of the Moon states that the Moon and Earth were "twins", forming side by side from a common cloud of gas and dust.
  3. 8. These objects are long, light streaks of pulverized rock that extend out of craters.
  4. 10. The large, smooth, dark areas of the Moon's surface are called this, from the Latin word for "seas."
  5. 11. Lunar scientists have detected only tiny quantities of gas above the Moon's surface. Most of the gas is this element.
  6. 14. When the Moon is more than half lit, it has this shape.
  7. 15. This theory of the origin of the Moon states that the Earth initially spun enormously faster than now and formed a bulge that ripped away from the Earth to become the Moon.
  8. 17. When an eclipse occurs, this happens at the time when the Moon's disk completely covers the Sun.
  9. 19. The difference in rocky material between the maria and highlands were discovered by samples collected by astronauts of this mission.
  10. 20. Sometimes an eclipse is _______, with only a portion of the Moon or the Sun ever being covered over.
  11. 22. These are the large circular pits located in bright areas on the Moon.
  12. 24. The second reason why the Moon lacks an atmosphere is because the Moon's ________ is too weak to retain gas for long.
  13. 25. When growing from a new phase, the Moon will next take this shape in its sequence of lunar phases.
  14. 26. A _____ ________ occurs whenever the Moon passes directly between the Sun and the Earth and blocks our view of the Sun.
  15. 27. A _____ ________ occurs when the Earth passes between the Sun and the Moon and casts its shadow on the Moon.
Down
  1. 2. As it orbits, the Moon keeps the same side facing the Earth. The Moon does turn on its axis but with a rotation period exactly equal to its orbital period. This condition is known as ___________ _____________.
  2. 3. These tides are abnormally large tides that occur during the Moon's new and full phases.
  3. 4. The bright areas that surround the maria are called _______________. This region differs from maria in brightness because they are composed of different rock types.
  4. 5. Since the Moon exerts a stronger force on one side of Earth and a weaker force on the other side of Earth, the difference in force overall is called this 3 word term.
  5. 6. Tides create forces on the Earth and the Moon that slow their rotation. This phenomenon is known as __________ __________________.
  6. 9. When talking about moon phases, at the beginning of the phases, the Moon grows or ______ from invisibility.
  7. 12. The Moon lacks this kind of field, suggesting that the core is at most partially molten. This is also due to a small amount of iron in its core.
  8. 13. This is known as the regular change in the height of the ocean and is caused mainly by the Moon.
  9. 16. These tides are not as extreme as normal high and low tides and occur during a Moon's first and third quarters.
  10. 17. The reason why we do not have an eclipse every lunar cycle is because of the ______ of the Moon's orbit, and because it remains fixed over time.
  11. 18. Sometimes, the Moon is so far away that its shadow does not reach the Earth. This will cause an eclipse where a ring of sunlight is seen as the Sun is setting. This is the name of this eclipse.
  12. 21. The first reason why the Moon lacks an atmosphere is because its interior is too cool to cause much _______ activity.
  13. 22. This theory of the origin of the Moon states that the Moon was originally a small planet orbiting the Sun. It approached the Earth and was captured by Earth's gravitational pull.
  14. 23. This term, meaning blanket of rock, consists of rock chunks and fine powder, the result of successive impacts breaking rock into smaller and smaller pieces.