1. & the Advent of the Scientific Method ASTRONOMY

2. ASTRO DAY 1

3. ASTRONOMY – SCIENTIFIC* STUDY OF SPACE Observations and explanations of celestial bodies, universe geography, movement, formation, energy… Includes cosmology, the study of the origin of and the behavior of the universe. * Not to be confused with Astrology a pseudoscience that uses celestial positions to predict events on Earth

4. Ancient Peoples Studied the Skies Built physical calendars - need to know the time of the year for planting & harvesting Community cultural centers - pagan celebrations of the solstices South America EuropeAsia North America

5. They Observed, and Inferred Scientific observatory (Incan) Mythical explanation (Mayan)

6. Observation 1= Sun, Moon, Stars in Motion http://vimeo.com/42576356

7. ASTRONOMY & WESTERN THOUGHT Observed: stars/moon/sun in motion but no evident Earth motion Inferred: geocentric universe- all object revolve in perfect circles around Earth Why circles?-the perfect geometric shape No experimentation; Aristotle's reasoned explanation was enough Aristotle 384-322 BC

8. WanderingStars Pose a Challenge Mars in Gemini December Mars in Leo July Planets Move Independent of Constellations Planet= wanderer in Latin

9. Wanderers Change Course Retrograde motion http://www.davidcolarusso.com/astro/ http://www.lasalle.edu/~smithsc/Astronomy/retrograd.html Planets Appear to move backwards (Retro) and then forward again What might cause this?

10. New Observations Dictate a New Hypothesis Ptolomy creates epicycles- orbits on orbits - to explain retrograde motion Many tries but cant make epicycles work (80+!) Still, a lasting hypothesis http://astro.unl.edu/naap/ssm/a nimations/ptolemaic.swf Ptolomy 140 AD

11. ASTRO DAY2

12. Need a New Hypothesis Unable to make epicycles work also Instead: Proposes the universe is heliocentric (sun centered); orbits are still perfect circles Waited until old age to publish, and then in Italian, not Latin why? Copernicus 1473-1543 AD http://science.larouchepac.com/kepler/newastronomy/part1/copernicus.html

13. Copernicus -no evidence it just made sense Its an optical illusion - the planets simply move at different speeds like passing a slower car on the freeway: it appears to go backwards Possible Explanation to Retrograde

14. The Advent Of Empiricism Used a telescope to generate evidence in support of heliocentric model 1. Discovered Jupiter had moons 2. Phases of Venus make clear Venus orbits the sun Gailileo Galilei 1564-1642 Venus phases diagram and animation

16. Data Makes The Difference Tycho Brahe 1546-1601 Johannes Kepler 1571-1630 Inferred the movement of the planetary orbits & made 3 laws Couldnt make sense of it 35 yrs of detailed data on planet positions Inherited and analyzed the data Video summary

17. Keplers 1 st Law of Planetary Motion: ovalness = eccentricity http://www.physics.sjsu.edu/tomley/Kepler12.html The planets orbits are ellipses with the sun at one of two foci

19. Keplers 2nd Law of Planetary Motion Planet must go faster when closer to sun and slower when farther from sun Almost worked out gravity! http://www.physics.sjsu.edu/tomley/Kepler12.html http://highered.mcgraw-hill.com/sites/0072482621/student_view0/interactives.html# The planets sweep out equal areas in equal time

20. Keplers 3rd Law of Planetary Motion p 2 =d 3 p = period in years d = distance in astronomical units (AU) 1AU = distance between sun and Earth (150,000,000km) boojum.as.arizona.edu