A Mysterious Visitor

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Across
  1. 2. object, idea, or event that is not named or described in detail.
  2. 10. unexpected; not familiar.
  3. 12. thing that can be seen and touched, but is not alive.
  4. 13. move past or to the other side of someone or something.
  5. 14. scientist who studies stars, planets, and other objects in space.
  6. 15. application of scientific knowledge for practical purposes, especially in industry.
  7. 16. or make something larger in amount, number, or degree.
  8. 19. or at a great distance.
  9. 20. state of the United States, located in the Pacific Ocean.
  10. 21. travel around an area to learn about it.
Down
  1. 1. in total.
  2. 3. to the space between the stars.
  3. 4. possibly.
  4. 5. keep doing something without stopping.
  5. 6. path that someone or something takes when moving.
  6. 7. or impossible to understand or explain; strange.
  7. 8. person who goes to see a place, person, or thing.
  8. 9. a feeling of surprise because it is unexpected.
  9. 11. rate at which someone or something moves or travels.
  10. 17. System：The system consisting of the Sun and the planets, moons, and other objects that orbit around it.
  11. 18. hit something with force, especially by accident.