1. Bellwork 9/7 If you have a survey for me, please turn it in to the basket on the side counter.
Please, take a puzzle from the bin on the front table.
Ponder…what causes scientific ideas to change?

2. Website & Safety

3. How does this relate to science?
Nature of Science
With the pieces provided, make a square.
How does this relate to science?

4. Origins of Modern Astronomy
Astronomy & Astrology
People & Tools

5. What is astrology?
Idea that positions of celestial bodies at the time of a person’s birth can determine their future
Based on 12 constellations that evenly divide up the sky
Constellations
Earth

6. Astrology was regarded as a scientific endeavor well into the 17th century
Used measurements of celestial body revolutions to create calendars
WHY?

7. Ultimately rejected as a science after being scientifically tested.
Causation vs. correlation
Evidence is not empirical
No proposed mechanism behind HOW celestial bodies affect terrestrial events

8. Development of Early Astronomy …it’s a process!
Ancient Greeks
Used philosophical arguments to explain
natural phenomena
Used some observational data
Most ancient Greeks held a geocentric view of the universe
"Earth-centered" view
Earth was a motionless sphere at the center of the universe

9. The Geocentric view had a LOT of issues…
A large problem was that it could not explain planets’ “backwards” motion

10. Aristarchus
( B.C.) was the first Greek to profess a Sun-centered, or heliocentric, universe
Also the first to suggest planets move in a retrograde motion
However, the geocentric theory would still dominate the Western world for nearly 2000 years…because a heliocentric model did not follow Aristotle’s views & was blasphemous
Where would be today if this theory was accepted…?

12. Claudius Ptolemy
A.D. 141
Geocentric model
Had trouble explaining retrograde motion, but came up with Deferents and Epicycles
Very complicated; difficult to measure
Europe
Became the most widely accepted model in Europe…because it followed Aristotle’s views

14. The universe according to Ptolemy, second century A.D.

15. Retrograde motion as explained by Ptolemy

16. Birth of Modern Astronomy …the process continues.
1500s and 1600s
Nicolaus Copernicus ( )
Concluded Earth was a planet
Constructed a model of the solar system that put the Sun at the center
used circular orbits for the planets
Ushered out “old” astronomy
Why did it take this long?

18. Tycho Brahe ( )
Precise observer with detailed notes on celestial bodies
Tried to find stellar parallax
the apparent shift in a star's position due to the revolution of Earth
Proposed that planets orbit in ellipses
Did NOT support the Copernican Heliocentric Theory
Science is NOT always a linear process…as history would have us think.

19. Johannes Kepler (1571-1630) Planets revolve around the Sun
Went against his religious beliefs , but the math worked.
Three laws of planetary motion
Help from Brahe
Ushered in “new” astronomy
“…the last scientific astrologer was the first astrophysicist”

20. Galileo Galilei (1564-1642) Supported Copernican theory
Used experimental data
Constructed an astronomical telescope in 1609
Four large moons of Jupiter
Planets appeared as disks
Phases of Venus
Features on the Moon
Sunspots

21. Sir Isaac Newton (1643-1727) Law of universal gravitation
Proved Kepler’s law of planetary elliptical orbits
Invention of calculus

22. “Contemporary” Astronomers/Cosmologists
Albert Einstein
Theory of Relativity
Edwin Hubble
Proposed the universe is expanding
Carl Sagan
Leader in research for extraterrestrial life
Stephen Hawking
Theorized that the universe began at a black hole
Neil DeGrasse Tyson
Research on stellar evolution

23. 49mfzd Timeline Activity Posted in our Google Classroom
Use the following code to access classroom:
49mfzd