Chapter 1
1. What is our comic address in order of increasing size?
- Our solar system is located a little more than half way from the galactic center to the edge of the galactic disk.
- Earth
- The solar System
- Milky Way Galaxy
- Local group
- Local supercluster
- Universe
Where is the Sun in the Milky Way?
-The sun is located in one of the Milky Way's outer arms, about 25,000 light years from the galactic center.
- Also in the Orion Arim, more than half way out of the galaxy
2. How many galaxies are in our local group?
- There are about 40 galaxies in our local group.
Are all the galaxies in our local group travelling away from each other?
- Yes, all galaxies in our local group are moving away …show more content…
6. What was Ptolemy’s cosmos like? How did he explain retrograde motion?
- Each planet moves around Earth on a small circle that turns upon a larger circle. A planet following this motion traces a loop as seen from Earth, with the backward proportion of the loop mimicking apparent retrograde motion.
7. What are epicycles and deferents?
- Each planet moves around Earth on a small circle that turns upon a larger circle. A planet following this motion traces a loop as seen from Earth, with the backward proportion of the loop mimicking apparent retrograde motion.
- ^Epicycles- the smaller circles; Deferents- the larger circles.
8. What was Copernicus’s cosmos like? Was he the first to describe a heliocentric cosmos? How did he account for retrograde motion?
- Sun-centered universe, with planets orbiting the sun, perfect circles
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