Space Race:

5. - The US space program that sent astronauts to the moon
6. - International Space Station, a habitable artificial satellite in low Earth orbit.
8. - A person trained to travel in space
11. - EVA, or Extravehicular Activity, when an astronaut leaves their spacecraft and moves into space
13. - Vehicle used for space travel
15. - First man in space, Yuri Gagarin

1. - The second US manned space program, which prepared astronauts for the Apollo missions
2. - National Aeronautics and Space Administration, the US space agency
3. - Soviet spacecraft that carried the first human into space
4. - Soviet and Russian spacecraft used for manned spaceflights and space station missions
7. - Vehicle that propels a spacecraft into space
9. - First man on the moon, Neil Armstrong
10. - The first artificial satellite launched into space by the Soviet Union
12. - Relating to the moon
14. - Russian term for astronaut