Across
- 2. A distinct luminescent part of interstellar medium
- 4. An alternative name for the universe
- 6. Particles that do not absorb, reflect, or emit light
- 10. A solid piece of debris from any object
- 13. A ocky, airless remnant
- 14. An extremely luminous active galactic nucleus
- 15. A global navigation satellite system
- 16. A unit of length equal to exactly 9,460,730,472,580.8 km
Down
- 1. The brightest and largest object in our night sky
- 3. The uppermost layer of our atmosphere
- 5. A sphere of gas held together by its own gravity
- 7. a powerful and luminous explosion of a star
- 8. A type of elementary particle and a fundamental constituent of matter
- 9. A celestial body that appears as a fuzzy head
- 11. One of the components of iron meteorites
- 12. A moon of Jupiter
- 13. A collective term referring to the atmosphere and outer space