Introduction to Astronomy The Oldest Science Created by Joshua Toebbe NOHS 2015 Intro to Astronomy: The oldest science Man kind has been looking at the stars for as long as we have existed. Some of the constellations we use today were named between 5 and 10 thousand years ago. It hasnt been until recently that humans have been able to look at the universe from outside of earth. Yet remarkable discoveries have been made long before now. Created by Joshua Toebbe NOHS 2015 Intro to Astronomy: The oldest science Earth revolves around the sun The order of the planets Our place in the galaxy All discovered by observations made from earth, but how Created by Joshua Toebbe NOHS 2015 Our Solar System Intro to Astronomy: The oldest science In ancient times man tried to find ways to track the stars and planets The Stonehenge in England in essential a pre-historic astronomical computer (albeit a little low-tech) Stonehenge was most likely used to calculate the positions of planets and stars The sky was used to navigate and as a calendar Created by Joshua Toebbe NOHS 2015 Hellenistic Greece Intro to Astronomy: The oldest science The Greeks inherited knowledge of the stars from the Babylonians and expanded upon it Predicting eclipses (Thales) Measuring earths circumference (Eratosthenes) And developing models of our solar system Heraclides developed the first geocentric (earth-centered) model circa 330 BCE Aristarchus developed the first heliocentric (sun-centered) model circa 270 BCE Created by Joshua Toebbe NOHS 2015 Geo vs Helio - Centric GeocentricHeliocentric Intro to Astronomy: The oldest science Created by Joshua Toebbe NOHS 2015 Our Solar System Intro to Astronomy: The oldest science Problems with the heliocentric model Earth is in motion No parallax is seen Geo-centric = Ego-centric Created by Joshua Toebbe NOHS 2015 Ptolemy Intro to Astronomy: The oldest science Ptolemy developed a model to explain retrograde motion But it was extremely complicated Ptolemy utilized a system of Epicycles and Deferents Created by Joshua Toebbe NOHS 2015 Ptolemy Intro to Astronomy: The oldest science Created by Joshua Toebbe NOHS 2015 The Renaissance Intro to Astronomy: The oldest science Copernicus (1500s) revived the heliocentric model to explain retrograde motion Created by Joshua Toebbe NOHS 2015 The Renaissance Intro to Astronomy: The oldest science Tycho Brahe (1580s) developed an interesting hybrid model of the solar system (kind of an offset geocentric model) Created by Joshua Toebbe NOHS 2015 The Renaissance Intro to Astronomy: The oldest science Kepler (1600s) was a student of Brahes and used his database to develop his three laws of planetary motion. The most notable of which stated that planets had elliptical, not circular orbits. Conclusively supported the heliocentric model. Created by Joshua Toebbe NOHS 2015 Cover image fromCorner image fromKepler Image from myhero.commyhero.com Brahe Solar system image from en.wikipedia.orgen.wikipedia.org History of Astronomy. University of Oregon. Retrieved 23 August Andrej rehak. [September 16, ]Ptolemys Model of the Universe. Retrieved 23 August 2015 https://www.youtube.com/watch?v=EpSy0Lkm3zM https://www.youtube.com/watch?v=EpSy0Lkm3zM Sources Intro to Astronomy: The oldest science Created by Joshua Toebbe NOHS 2015