Stars

1. a stream of high-speed, ionized particles flowing outward through the solar system from the Sun's corona
5. a cloud of interstellar dust or gas or both, which collapses on itself as a result of its own gravity
6. a sudden eruption of particles and radiation from the surface of the Sun
9. a nuclear reaction in which an atomic nucleus splits into smaller, lighter nuclei releasing energy
10. relatively cool, dark spots appearing on the surface of the photosphere
11. brightness an object would have if it were placed at a distance of 10 pc
12. energy output from the surface of a star per second, measured in watts
15. collapsed, dense core of a star that forms quickly while its outer layers are falling inward
16. the hot, condensed, disk-shaped object at the center of a collapsing cloud

2. ancient Greek classification system based on how bright a star appears to be
3. two stars gravitationally bound together and orbiting about a common center of mass
4. small, extremely dense remnant of a star whose gravity is so immense that not even light can escape its gravity field
7. group of stars that forms a pattern in the sky
8. massive explosion that occurs when the outer layers of a star are blown off
9. a nuclear reaction in which lightweight nuclei combine into heavier nuclei
13. top layers of the Sun’s atmosphere
14. a spinning neutron star that exhibits a pulsing pattern massive