1. History of Astronomy
Chapter 22
Section 1

2. ASTRONOMY - study of the universe Early Ideas 1
ASTRONOMY - study of the universe Early Ideas 1. Geocentric View - Began with the Greeks - Idea that Earth is round and the sun & planets orbit around the Earth. 2. Heliocentric View - Idea that the planets orbit the sun

3. Geocentric and Heliocentric Models

4. Important Astronomers 1
Important Astronomers 1. Copernicus - concluded that Earth is a planet - concluded planets orbit the sun in a solar system 2. Kepler - Discovered 3 Laws of Planetary Motion 1) Planets travel in elliptical patterns 2) Planets move quicker near the sun 3) Planet’s time to orbit the sun & its distance from the sun is proportional * Planet distance can be determined with orbit time

5. Planet Revolution

6. 3. Galileo - 1st to use a telescope for Astronomy Discoveries 1) Found 4 of Jupiter’s moons - disproved Geocentric view 2) Discovered planets are circular disks 3) Venus has phases like our moon 4) Moon is cratered and not smooth 5) Sun has dark spots (sunspots) 4. Sir Isaac Newton - 1st to formulate & test Law of Gravity

7. Gravity’s Influence on Orbits

8. Tools of Astronomy
Chapter 24
Section 2

9. Telescopes 1) Refracting Telescopes
- using a lens to bend light to a focus

10. 2) Reflecting Telescopes - using a mirror to focus light
2) Reflecting Telescopes - using a mirror to focus light * Easier to build large mirrors instead of large lens*

11. 3) Radio Telescopes - using an antenna to detect invisible radio waves