Space

3. sixth planet from the Sun, second-largest in our solar system
5. A natural or artificial body that orbits a planet.
7. A space that is empty of matter
9. space object made of ice and dust with a long, bright tail.
11. Stellar explosion
14. An irregularly shaped rock that orbits a star.
16. A system of millions or billions of stars, gas, and dust held together by gravity.
18. The largest planet in our solar system.

1. The gravitationally curved path of an object around a point in space.
2. Occurring between stars
3. System The collection of eight planets and their moons in orbit round the sun.
4. Gas and dust cloud
6. A person trained to travel in a spacecraft.
8. planet fourth in order from the sun and conspicuous for its red colour
10. NASA's current program which aims to land humans on the Moon again.
12. A force that causes all objects with mass to attract to one another.
13. Sun's outer atmosphere
15. The flight path of a space vehicle
17. Lacking perceived gravity