1. 2. a broad luminous irregular band of light that stretches completely around the celestial sphere
  2. 4. fixed a luminous point in the night sky which is a large, remote incandescent body like the sun
  3. 6. a person who is trained to travel in a spacecraft
  4. 10. a celestial body moving in an elliptical orbit around a star
  5. 11. a cylindrical projectile that can be propelled to a great height or distance by the combustion of its contents, used typically as a firework or signal
  6. 12. the star around which the earth orbit
  7. 14. the force that attracts a body toward the center of the earth, or toward any other physical body having mass
  8. 15. coherent, typically large body of matter with no definite shape
  9. 18. a vehicle for exploring the surface of a planet or moon
  10. 19. the science and technology of human space travel and exploration
  11. 20. has a collection of eight planets and their moons in orbit around the sun
  1. 1. a power-driven aircraft that is kept buoyant by a body of gas
  2. 3. the study of the movements and relative positions of celestial bodies interpreted as having an influence on human affairs and the natural world
  3. 5. the action of rotating around an axis or center
  4. 7. the systematic study of the structure and behavior of the physical and natural world through observation, experimentation, and the testing of theories against the evidence obtained
  5. 8. the science or practice of travel through the air
  6. 9. start or set in motion
  7. 12. shuttle a rocket-launched spacecraft, able to land like a powered aircraft, used to make repeated journeys between the earth and earth orbit.
  8. 13. glider designed for sustained flight
  9. 16. the basic unit of a chemical element
  10. 17. engineers evaluate designs to see that the products meet engineering principles.