Across
- 5. The center of a galaxy
- 7. The relation between apparent velocity recession and distance
- 9. A chaotic mix of gas, dust, and stars with no obvious shape
- 10. A model that captures the image a galaxy's core
- 12. Round, contain no visible gas, dust or bright stars
- 13. Objects used to map spiral arms
- 14. Using such a graph to find the mass of the galaxy
- 15. When you look at a distant galaxy, you look back into the past by an amount
Down
- 1. An obvious disk and nuclear bulge but little to no visible gas and dust
- 2. Objects that find that distance to a galaxy
- 3. Huge clouds of dust or distant radio galaxies
- 4. A disk and spiral arms
- 6. Roughly two-thirds of all spiral galaxies
- 8. The slope of the line
- 11. The unit that astronomers use