Age of EnlightenmentA cultural movement ofintellectuals in the 17th and18th centuries, which beganfirst in Europe and later in theAmerican colonies. Its purposewas to reform the way ofthinking using reason, challengerelated to tradition and faith,and advance knowledgethrough the scientific method.It promoted scientific thoughts,skepticism and intellectualinterchange and completelyopposed any kind ofsuperstition, intolerance andsome abuses of power by thechurch and the state.
It starts with Scientific Revolution• The Enlightenment starts with the Scientific Revolution• People started to question ideas that had been accepted as facts for hundreds of years
Back then, all knowledgecame from the Catholic Church The Catholic Church and the Bible were the source of what was true and false in the world
Also…Ancient Greekand RomanPhilosophers,such as Aristotle,said what wastrue about thenatural world
Scientific Revolution • Was a new way of looking at the natural world • Traditional ideas were found to be wrong through observation, experimentation, and theories
GEOCENTRIC GEO = EARTH CENTRIC = CENTERThey believed the Earth was the center of the universe
HELIOCENTRIC HELIO = SUN CENTRIC = CENTERThey believed the sun is the center of the universe
AristotleThe spherical Earth isat the center of theuniverse, and all otherheavenly bodies areattached to 47–56transparent concentricspheres which rotatearound the Earth.
Ptolemy Ptolemy argued that the Earth was in the center of the universe, from the simple observation that half the stars were above the horizon and half were below the horizon at any time
Nicolaus CopernicusAll the spheres revolveabout the sun as their mid-point, and therefore the sunis the center of the universe.What appear to us asmotions of the sun arise notfrom its motion but fromthe motion of the earth andour sphere, with which werevolve about the sun likeany other planet. The earthhas, then, more than onemotion.
Johannes KeplerKeplers Three Laws can be usedto describe the motion of thePlanets:1. The Planets move in orbitsabout the Sun that are ellipses2 . The planets move such thatthe line between the Sun and thePlanet sweeps out the same areain the same area in the same timeno matter where in the orbit.3. The square of the period of theorbit of a planet is proportional tothe mean distance from the Suncubed.
Tycho BraheA Danish astronomer who made measurements of the planet andstars. His measurements were the most accurate that had yet beenmade.Tycho proposed a system in which all of the planets except for Earthorbited about the Sun. He claimed that the Sun still orbited about theEarth, however.
Sir Isaac Newton Newton derived the law of gravitation between two masses. Since the Sun was the most massive object in the planetary system, all of the planets would naturally be attracted to it and revolve around it, in the same manner as the Moon revolves around the Earth.
Galileo GalileiGalileos observationsstrengthened his belief inCopernicus theory thatEarth and all other planetsrevolve around the Sun.Most people in Galileostime believed that the Earthwas the center of theuniverse and that the Sunand planets revolvedaround it.
GalileoGalileo wrote about hisobservations and thusangered the RomanCatholic Church. TheChurch eventually placedhim under house arrest.The Inquisition was thetribunal of the RomanCatholic Church at thistime. The Inquisitionmade Galileo kneelbefore them and confessthat the heliocentrictheory was false.
The InquisitionA group of decentralized institutions within the judicialsystem of the Roman Catholic Church whose aim was to"fight against heretics". It started in 12th-century France tocombat the spread of heresy and error, and was laterexpanded to other European countries.
“Heresy” a: adherence to a religious opinion contrary to church dogma b: denial of a revealed truth by a baptized member of the Roman Catholic Church c: an opinion or doctrine contrary to church dogma a: dissent or deviation from a dominant theory, opinion, or practice b: an opinion, doctrine, or practice contrary to the truth or to generally accepted beliefs or standards
Galileo was right all alongIn 1992, the RomanCatholic Church finallyrepealed the ruling ofthe Inquisition againstGalileo. The Churchgave a pardon toGalileo and admittedthat the heliocentrictheory was correct. Thispardon came 350 yearsafter Galileos death.
Geocentric• Key Ideas: – “Geo” = Earth – “Centric” = Center • “Earth-centered” – Earth is the center of the solar system – Earth is stationary (not moving) and everything is moving around us In your notes, draw a picture of what the geocentric model looks like…
Geocentric models• Key Limitations: – Did not explain the apparent motions of some planets (for example, Mars) – Did not explain all of Earth’s motions, including how a freely- swinging pendulum moves
Heliocentric • Key Ideas: – “Helio” = Sun – “Centric” = Center • “Sun-centered” – The Sun is the center of the solar system – Earth rotates on its own axis AND revolves around the Sun In your notes, draw a picture of what the heliocentric model looks like…
Heliocentric modelsKey Limitations: The early models used circular orbits did not explain the apparent motions of planets (BUT… once elliptical orbits and planets’ orbital speeds were added to the model, the planets’ apparent motions could be explained and even predicted!)