Across
- 1. the middle feature of our galaxy
- 3. the standard candle Hubble used to determine Andromeda was a galaxy
- 4. an object used to determine distance by comparing absolute and apparent magnitudes
- 7. a cluster of stars that orbit the Milky Way
- 10. hubble's Tuning Fork's original purpose: determining the __ of galaxies
- 11. unknown source of gravity around galaxies
- 14. active star formation takes place here in a spiral galaxy
- 15. method used for nearby objects' distance measurement
- 17. Hubble discovered that the Universe is doing this
- 18. most galaxies are ___-shifted
- 19. globular clusters exist here
- 20. Galaxy we live in
Down
- 2. light bending due to gravity
- 5. the kind of galaxy not included in Hubble's Tuning Fork
- 6. the color of active stellar formation
- 8. the kind of galaxy ours is
- 9. what lies in the center of galaxies
- 12. the two kinds of spirals: regular and ___
- 13. a small group of galaxies
- 16. how we can determine the distance of a nearby star with geometry
- 19. the kinds of elements absent in the early Universe