Cosmic Journeys

Across

3. Mathematical subset within a vector space

4. Vessel designed for interstellar travel

6. Bright celestial traveler with a tail

8. Brief summary of main points

9. Path of a planet around star

13. Falling space rock streaking through sky

14. Ordinary person without noble rank

15. Young animal about one year old

Down

1. Return to atmosphere after spaceflight

2. Field professional who treats injuries

5. North Star guiding sailors at night

7. Obscuring of one celestial body by another

10. Calm someones doubts or fears

11. Relating to the universe beyond Earth

12. Massive system of stars and planets