Knowledge and Understanding of the Solar System

  • Period: 100 to 160

    Ptolemy

    Ptolemy was an astronomer and mathematician. He believed that the Earth was the centre of the Universe. The word for Earth in Greek is geo, so we call this idea a "geocentric" theory.
  • Period: 1501 to 1503

    Nicolaus Copernicus

    Nicolaus Copernicus formulated a model of the universe that placed the Sun rather than the Earth at the center of the universe.
  • Period: 1581 to

    Galileo Galilei

    His discovery of the four most massive moons of Jupiter, now known as the Galilean moons.
  • Period: 1582 to

    Edmond Halley

    He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720. From an observatory, he constructed on Saint Helena. Halley recorded a transit of Mercury across the Sun.
  • Period: to

    Johannes Kepler

    Johannes Kepler discover Kepler's three laws of planetary motion.
  • Period: to

    William Herschel

    William Herschel discovered Uranus.
  • Period: to

    Discovery of the first four asteroids

    Piazzi named it after Ceres, the Roman goddess of agriculture.
  • Period: to

    Urbain Le Verrier

  • Period: to

    Clyde Tombaugh

    Discovered Pluto
  • Period: to

    Voyager 1