Across
- 2. a system of millions or billions of stars
- 5. theory stating the universe is expaniding
- 7. an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other.
- 8. the chemical element of atomic number 1
- 9. the displacement of spectral lines toward longer wavelengths
Down
- 1. become or make larger or more extensive.
- 3. contains a vast number of galaxies
- 4. the property of matter and radiation which is manifest as a capacity to perform work
- 6. any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources.
- 8. the chemical element of atomic number 2