space

6. A state of very weak gravity.
10. The path of an object moving through space.
12. A vehicle designed for space flight.
13. The science of getting ships, aircraft, or spacecraft from place to place.
15. Tunnels and caves formed by lava movement in the moon's distant past.

1. a bowl shaped depression on the moon
2. A quantity with both magnitude and direction, such as velocity, acceleration, thrust, lift, drag, momentum, or torque.
3. A proposed explanation for an observation.
4. A vector quantity that includes the speed and direction of an object.
5. Weightlessness.
7. A path described by one body in its revolution about another.
8. A vehicle, missile, or aircraft which obtains thrust by the reaction to the ejection of fast moving exhaust from within a rocket engine.
9. A chemical mixture that is burned to produce thrust.
11. a person who rides in a space vehicle
14. International Space Station