Across
- 3. – the measure of the observed visible brightness of a star
- 6. – luminous globe of gas which produces its own heat and light by nuclear reaction made of mostly
- 8. dense areas continually rise; the more dense areas continually sink, creating a cyclical current
- 10. – an envelope of mixed gases held to the Earth by gravity; the most dense gases are near the
- 14. – the long-term pattern of weather in an area
- 16. diagram – a diagram that shows the relationship between the brightness, surface
- 17. – a system of stars and associated matter held together by gravitational attraction
- 18. – observations of galaxies moving away from each other and our own Milky Way galaxy
- 21. – clouds of dust and gas; site of star formation; remains of dead or dying stars
Down
- 1. current – when temperature differences cause liquids and gases (fluids) to expand and move; the
- 2. and color of stars
- 4. microwave background – electromagnetic radiation that remains from the Big Bang and early stages of
- 5. which began and is still expanding
- 7. universe
- 9. hole – a region in space where gravity is so strong that even light cannot escape
- 11. of the Earth
- 12. Bang theory – a scientific theory concerning the early development and shape of the universe from a dense
- 13. Way galaxy – the galaxy which contains our Sun and its solar system, including Earth
- 15. mass – a body of air that has about the same temperature and humidity throughout
- 19. and helium gas
- 20. – total amount of light (energy) emitted by a star or other celestial body