The Universe

6. a large mass of collapsing gas and dust located in the universe that forms stars and planets
8. a galaxy with a bulge in the middle and arms that spiral outward in a pinwheel pattern
10. Electromagnetic waves with the shortest wavelengths and highest frequencies
11. stellar nebula, massive star, red supergiant, supernova, neutron star or black hole
12. A galaxy shaped like a round or flattened ball, generally containing mostly older stars
13. stellar nebula, average star, red giant, planetary nebula, white dwarf

1. A ball of hot gas, primarily hydrogen and helium, that undergoes nuclear fusion.
2. A galaxy that does not have a regular shape
3. the complete range of electromagnetic waves placed in order of increasing frequency
4. A gigantic explosion in which a massive star collapses and throws its outer layers into space
5. A huge cloud of gas that is created when the outer layers of a red giant star drift out into space
7. Electromagnetic waves with the longest wavelengths and lowest frequencies
9. Electromagnetic radiation that can be seen with the unaided eye