Across
- 2. A giant cloud of dust and gas in space; often a "nursery" for new stars.
- 3. Electromagnetic radiation left over from an early stage of the universe.
- 6. A scatter plot of stars showing the relationship between luminosity and temperature.
- 9. The force that governs the motion of objects in the solar system and keeps planets in orbit.
- 10. Horizon The boundary surrounding a black hole from which no light or matter can escape.
- 12. Sequence The stage where a star spends most of its life, fusing hydrogen into helium.
- 13. What stars like the Sun become after they have exhausted their nuclear fuel.
- 15. Spectrum The range of light frequencies (visible and invisible) used to study the composition of stars.
Down
- 1. The displacement of spectral lines toward longer wavelengths in radiation from distant galaxies (evidence the universe is expanding).
- 4. The measure of the brightness of a star or other celestial body.
- 5. A powerful and luminous stellar explosion that occurs during the last evolutionary stages of a massive star.
- 7. Matter A component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity.
- 8. A large, reddish star late in its life cycle that has expanded and cooled.
- 11. An object that orbits a planet or star (can be natural like the Moon or artificial).
- 14. The tendency of an object to resist a change in motion.