Vocab crossword puzzle 2

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Across
  1. 3. our planet
  2. 6. an object's spinning motion about its own axis 1
  3. 9. the point at which the atmosphere's pressure is one bar
  4. 11. the theory of the science of physical and logical laws with respect to any natural body in the sky especially at night.
  5. 12. the region beyond the earth's atmosphere containing the other planets of the solar system, stars, galaxies, etc
  6. 13. any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources.
  7. 14. a doughnut-shaped ring of icy objects around the Sun, extending just beyond the orbit of Neptune from about 30 to 55 AU
  8. 16. the big rock that orbits our planet
  9. 19. an object's spinning motion about its own axis 2
  10. 20. the extremely hot center of Earth, another planet, or a star.
Down
  1. 1. the angle between the plane of the earth's equator and the plumb line (direction of gravity) at a given point on the earth's surface
  2. 2. the diameter measured by an observer at a specific distance from the object
  3. 4. the convention for measuring angles on the sky
  4. 5. the force by which a planet or other body draws objects toward its center
  5. 7. an invisible line around which an object rotates, or spins
  6. 8. cosmic snowballs of frozen gases, rock, and dust that orbit the Sun
  7. 10. a small rocky body orbiting the sun
  8. 12. a small number of stars that orbit each other, bound by gravitational attraction
  9. 15. the object's orbital motion around another object
  10. 17. a regular, repeating path that one object takes around another object or center of gravity
  11. 18. a 4.5 billion-year-old yellow dwarf star – a hot glowing ball of hydrogen and helium – at the center of our solar system