Across
- 5. A condition where bones become weak and brittle
- 7. The force that slows motion when two surfaces rub together
- 10. The part of the body that pumps blood
- 12. A measurement of the amount of gravitational pull
- 13. Low blood pressure; often experienced by astronauts returning to Earth
- 14. The part of the body that helps control balance(2 words)
- 15. A person trained to travel in space
Down
- 1. The amount of matter in an object
- 2. the air surrounding Earth
- 3. force that pulls object's towards Earth's center
- 4. the space station where astronauts live and work in orbit
- 6. A famous astronaut who spent nearly a year in space
- 8. very weak gravity experienced in space
- 9. How tightly packed matter is in a substance
- 11. Gas essential for human survival