ACROSS

1. First manned shuttle ever launched
4. First part of another name for an alien
5. Second part of an alien
8. The force that keeps us connected to the earth's surface
10. Solid Rocket _____________
11. Density of an object
12. Man who defined gravity as we know it today
15. First US man in space, John ______
16. Planetary body with 1/6 th earth's gravity
18. One of the last stage of a star's life
19. Instrument used to explain how a ball can fall around the earth

DOWN

2. Travel around the earth
3. Miss Baker and Able
4. Large, orange fuel storage for Main Engines
6. The bulk of a star's existence
7. Hunter constellation in the winter sky 9. Cosmonaut _____ Gagarin
13. A stream of charged particles emitted from the sun
14. Type of creature that battled the hunter in the night sky
17. Organization responsible for many of the advancement made in space exploration