The scientific revolution

The Scientific Revolution: Brahe, Kepler, and Descrates

  • Jan 1, 1546

    Tycho Brahe Born

    Tycho Brahe Born
  • Period: Jan 1, 1546 to


    Facts and accomplishments of Brahe.
    Brahe's ideas about his data were not always correct, but the quality of the observations themselves was central to the development of modern astronomy.
  • Period: Jan 1, 1571 to


    Facts and accomplishments of Kepler.
    Frail of body, but robust in mind and spirit, Kepler was scrupulously honest to the data.
  • Dec 27, 1571

    Johannes Kepler Born

    Johannes Kepler Born
    Kepler played a key role in the scientific revolution that occurred in the 17th century, contributing a number of scientific breakthroughs including his famous laws of planetary motion.
  • Jan 1, 1572

    Brahe's observations of a supernova

    Brahe's observations of a supernova
    This was a "star" that appeared suddenly where none had been seen before, and was visible for about 18 months before fading from view. Since this clearly represented a change in the sky, prevailing opinion held that the supernova was not really a star but some local phenomenon in the atmosphere (remember: the heavens were supposed to be unchanging in the Aristotelian view). Brahe's meticulous observations showed that the supernova did not change positions with respect to the other stars
  • Jan 1, 1577

    Brahe made careful observations of a comet

    Brahe made careful observations of a comet
    By measuring the parallax for the comet, he was able to show that the comet was further away than the Moon. This contradicted the teachings of Aristotle, who had held that comets were atmospheric phenomena ("gases burning in the atmosphere" was a common explanation among Aristotelians). As for the case of the supernova, comets represented an obvious change in a celestial sphere that was supposed to be unchanging; furthermore, it was very difficult to ascribe uniform circular motion to a comet.
  • Jan 1, 1582

    Brahe's stellar parallax

    Brahe's stellar parallax
    -the earth was motionless at the center of the Universe, or
    -the stars were so far away that their parallax was too small to measure.
    Not for the only time in human thought, a great thinker formulated a pivotal question correctly, but then made the wrong choice of possible answers: Brahe did not believe that the stars could possibly be so far away and so concluded that the Earth was the center of the Universe and that Copernicus was wrong.
  • Brahe proposed a model of the Solar System

    Brahe proposed a model of the Solar System
    Brahe proposed a model of the Solar System that was intermediate between the Ptolemaic and Copernican models (it had the Earth at the center). It proved to be incorrect, but was the most widely accepted model of the Solar System for a time.
  • Kepler's Mysterium cosmographicum

    Kepler's Mysterium cosmographicum
    (The Sacred Mystery of the Cosmos -1596)
  • Rene Descartes born

    Rene Descartes born
  • Period: to


    Facts and accomplishments of Descartes. Rene Descartes was a respected philosopher, scientist and mathematician. He used new methods of investigating nature and he invented analytic geometry. He was the first philosopher to describe the physical universe in terms of matter and motion. He created three major works: Discourse on Method, Meditations on First Philosophy, and Principles of Philosophy.
  • Period: to

    Descartes continued

    He claimed that the world was created by God and that it was made of two substances: matter and spirit. Matter was the physical universe and spirit was the human mind. He considered that perhaps God or an evil spirit was constantly tricking his mind causing him to believe what was false. His theories of knowledge and of the relation between mind and matter influenced many later philosophers. Rene Descartes is considered the father of modern philosophy.
  • Tycho Brahe dies

    Tycho Brahe dies
    Brahe is thought to have died when he contracted a urinary infection while attending a banquet hosted by a baron in Prague in which he drank extensively but felt that etiquette prevented him from leaving the table to relieve himself before the host left
  • Kepler's Astronomia nova

    Kepler's Astronomia nova
    (New Astronomy - 1609)
    stated Kepler's First 2 Laws of Planetary Motion
  • Johannes Kepler devised Kepler's First 2 Laws of Planetary Motion

    1. planets travel in elliptical orbits around an off-centre sun.
    2. the speed of a planet's orbit depends on its distance from the sun. when a planet's close to the sun it, orbits faster. when it's further away from the sun, it travels slower
  • Kepler's Harmonice Mundi

    Kepler's Harmonice Mundi
    (Harmony of the Worlds - 1619)
    stated Kepler's 3rd Law of Planetary Motion
  • Johannes Kepler devised Kepler's 3rd Law of Planetary Motion

    1. the farther a planet or dwarf planet is from the sun, the longer its orbit
  • Kepler's Epitome astronomiae Copernicanae

    Kepler's Epitome astronomiae Copernicanae
    (Epitome of Copernican Astronomy - published between 1618 and 1621)
    This was his most influential work and discussed all of heliocentric astronomy in a systematic way
  • Johannes Kepler dies in Regensburg

    Johannes Kepler dies in Regensburg
  • Rene Descartes dies

    Rene Descartes dies
  • Scientific method thanks to Descartes

    Scientific method thanks to Descartes
    It was the scientific method that emerged from the work of Descartes (1596-1650), Sir Isaac Newton (1642-1727), and Joseph Priestly (1733-!804)