Across
- 4. Useful unit for measuring the distances between astronomical objects
- 5. Region of space containing a huge amount of mass compacted into an extremely small volume
- 8. Explosive death of a star whose energy output causes its expanding gases to glow brightly for weeks or months
- 11. Lightest and most abundant chemical substance in the universe
- 13. Cloud of gas and dust located between stars and/or surrounding stars
- 16. Planet that orbits a star other than the Sun
- 17. Matter that is too dim to be detected by telescopes, astronomers infer its existence by measuring its gravitational influence
- 18. Collection of stars, gas, dust, and dark matter bound together by gravity
- 19. Invisible, nearly massless subatomic particles that are electrically neutral and can travel at nearly the speed of light without being deflected by magnetic fields or absorbed by matter
Down
- 1. One of the five points at which an artificial satellite or small cosmic object, like an asteroid, can remain in a position of equilibrium
- 2. Sixth planet in the Solar System, noted for its obvious ring structure
- 3. Study and interpretation of a celestial object’s spectrum
- 6. Stretching of light to longer, redder wavelengths as it moves through space due to the expansion of the universe
- 7. Distance between two wave crests
- 9. Process by which ions are produced, typically by collisions with other atoms or electrons, or by absorption of electromagnetic radiation
- 10. Explosion caused when two neutron stars or a neutron star and a black hole merge. Short gamma-ray bursts are also thought to originate from such a merger
- 12. Neutron star that emits rapid and periodic pulses of radiation
- 14. Theory of physics that describes the dynamical behavior of matter and energy
- 15. Part of the electromagnetic spectrum that has slightly lower energy than visible light, but is not visible to the human eye