Across
- 2. Regions of gas and dust plus young stars that wind outward from the central area bulge.
- 5. an American astronomer who played a crucial role in establishing the field of extragalactic astronomy
- 6. small galaxy containing a few million to a few billion stars.
- 9. Oval or egg shaped galaxy with older stars and little gas and dust.
- 10. a spiral galaxy with a central bar-shaped structure composed of stars.
Down
- 1. Galaxy that is neither spiral nor elliptical.
- 3. Very large group of stars held together by gravity; a few million to a few billion stars.
- 4. a spiral galaxy approximately 2.5 million light-years from Earth. Also known as Messier 31
- 7. Rotating type of galaxy with a central bulge and spiral arms with stars, gas, and dust.
- 8. a hypothetical kind of matter that cannot be seen with telescopes but accounts for most of the matter in the universe.