Astronomy Topic 5, Part 2

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Across
  1. 1. A greek who split the world into imperfect Earth and perfect heavens
  2. 3. The Egyptians built these to align with the stars
  3. 6. Ptolemy used this to explain retrograde motion
  4. 8. Planets that are closer to the Sun than the Earth
  5. 9. Causes misalignement of monuments over 26000 years
  6. 11. The Earth is between the Sun and a Superior planet
  7. 12. Reintroduced heliocentric theories on his deathbed
  8. 13. Ptolemy's 'circles' moved along this main orbital path
  9. 15. Observed the moons of Jupiter and phases of Venus
  10. 16. An (distant) object is totally blocked by another body
  11. 18. A planet lies on the furthest side of the Sun to the Earth
  12. 20. Used his mentors maths to create the Laws of Planetary Motion
  13. 22. A 90 degree angle is formed between the inferior planet, the Sun and the Earth
Down
  1. 2. The Sun is between an inferior planet and the Earth
  2. 4. An inferior planet is between the Sun and the Earth
  3. 5. The accepted model of the Solar System
  4. 7. The object moves across the Sun in its orbit, as seen from Earth
  5. 10. The Earth's wobble is caused by the Sun, Jupiter and...
  6. 14. Ptolemy's model included an off centre Earth and an...
  7. 17. Made observations of Mars over 20 years
  8. 19. Planets that are further from the Sun than the Earth
  9. 21. Ancient Britons built this as calendar to align with the direction of the Summer Solstice sunrise