Space

3. A state of very weak gravity.
4. Tunnels and caves formed by lava movement in the moon's distant past. These tubes can serve as shelter from meteorites, radiation, and extreme temperatures.
8. The path of an object moving through space.
10. The mechanical coupling of two or more human-made orbiting objects.
11. A bowl-shaped depression formed in the soft soil of the moon by the impact of a meteorite or other object.
14. A vector quantity that includes the speed and direction of an object.
15. A fixed or adjustable vane or airfoil affixed longitudinally to an aerodynamically or ballistically designed body for stabilizing purposes.
16. in the u.s.,a person who rides in a space vehicle.

1. A chemical mixture that is burned to produce thrust.
2. A proposed explanation for an observation. An educated guess which forms a basis for a test.
5. The path of an object moving through space.
6. A vehicle for driving over rough terrain.
7. Fine, greyish dust and soil that covers the surface of the moon. Formed by constant pounding of the surface by impacts, the regolith can be between 2 meters and 20 meters deep.
9. The arrangement of the natural and artificial physical features of an area.
12. The locus of all points in the plane at which the sum of the distances from a fixed pair of points is a given constant.
13. A quantity with both magnitude and direction, such as velocity, acceleration, thrust, lift, drag, momentum, or torque.