Astrology

3. the outermost layer of the Sun's atmosphere
5. combine to keep the planets in orbit around t he sun
7. the middle layer of the Sun's atmosphere
8. a large group of older stars
11. the gas giants are composed mainly of hydrogen
12. matter that does not give off radiation
14. how bright a star really is
16. regular rise and fall of the ocean waters
17. an object whose surface gravity is so great that even electromagnetic waves traveling at the speed of light, cannot escape from it.

1. The closest star to the sun. It is roughly 4.3 light years away
2. the very bright stars at the upper right of the H-R diagram
4. The _____________ of the Sun's atmosphere that is visible from the earth's surface
6. dusty pieces of ice and rock that partially vaporize when they pass near the sun
9. the brightness of a star that appears from Earth
10. a star system with two stars
13. planets that are similar to the Earth
15. the distance that light travels in a vacuum in a year. It is roughly 9.5 trillion kilometers