p2 sophia V astronomy time line

By sophiav
  • 200

    Ptolemy

    Ptolemy
    (100? - 170?) He proposed a geocentric, or earth centered, universe in which the planets and fixed stars were embedded in concentric crystilline spheres that revolved around the Earth.
  • Jan 1, 1564

    Gallileo Galilei

    Gallileo Galilei
    (1564 -1642) Galileo was the first astronemer to use a telescope. He gave visual evidence that suppored the Coprecornian theory of a heliocentric universe.
  • Jan 13, 1571

    Johannes Kepler

    Johannes Kepler
    (1571 - 1630) Johannes Kepler discovered that the planets (including Earth) orbit the sun in an oval shape. He also explained how humans see and demonstrated what happens to light when it enters a telescope (and designed one of his own.)

  • Nicholas Copernicus

    Nicholas Copernicus
    Nicholas Copernicus thought that earth rotates on its axix through the north and south ples once a "siderial' day. He thought the earth orbited around the sun once every "siderial" year.

  • Sir Isaac Newton (universal law of gravity)

    Sir Isaac Newton (universal law of gravity)
    (1642 - 1727) Newton explained that every object in the universe attracts every other object with a force directed along the line of centers for the two objects that is proportional to the product of their masses and inversly proportional to the square of the separation between the two objects (universal law of gravity.)

  • sir isaac newton (motion and inertia)

    sir isaac newton (motion and inertia)
    Newtons first law of motion is aften stated as: an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. He also explained inertia, which is the resistance an object has to a change in its state of motion.