vocab crossword

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

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