23.18: Beyond the Solar System- Challenge 3
- Page ID
- 6267
- 1. The closest galaxy to ours is the ___.
- Andromeda Galaxy
- 2. A ___ galaxy has pinwheel-like arms and rotates around a central bulge.
- spiral
- 3. The three types of galaxies are ___.
- spiral, elliptical, and irregular
- 4. Our solar system is located ___.
- within one of the spiral arms of the Milky Way
- 5. The ___ of the Milky Way contains the oldest stars.
- halo
- 6. There is a ___ in the center of the Milky Way.
- black hole
- 7. Redshift is ___.
- the phenomenon in which absorption bands are shifted towards the red end of the spectrum
- 8. According to the Doppler Effect, ___.
- as waves moves closer to you, the waves pack closer together, and vice versa
- 9. Hubble's Law states that ___.
- the farther away a galaxy is, the faster it is moving away from us
- 10. ___ and ___ are the most abundant gases in the universe.
- Hydrogen; helium
- 11. During the immediate aftermath of the Big Bang, hydrogen nuclei collided and fused into ___ nuclei.
- helium
- 12. According to the Big Bang Theory, the universe formed ___ years ago.
- 13.7 billion