Ancient Astronomers

  • 240 BCE

    Eratosthenes

    • When most people believed the world was flat, he used the sun to measure the size of the round Earth.
    • 240 B.C.
    • This discovery was a real game changer onto how scientists and everyone else viewed the Earth and other planets.
  • 100

    Claudius Ptolemy

    • He set up a model of our solar system.
    • Around 100 AD
    • This was the first model of our solar system.
  • 1543

    Nicolaus Copernicus

    • Came up with a different way to view the Universe. His heliocentric system put the Sun at the center.
    • 1543
    • This was important because this was how astronomers and scientists believed the Universe was like for many years
  • 1546

    Tycho Brahe

    • He was very wealthy so he contributed to more presice instruments before the invention of the telescope
    • 1546-1601
    • This was important because this was the first big step to creating the telescope.
  • Johannes Kepler

    • He determined that the sun travels in ellipses, not circles.
    • 1609
    • The planets are closer and farther away from the sun at different points in the year.
  • Sir Isaac Newton

    • He calculated the three laws describing the forces between objects what are now called Newton’s Laws.
    • 1666
    • These are important because they tie into almost everything we see in our life.
  • Albert Einstein

    • He came up with the theory of relativity and the equation E=MC^2.
    • 1905
    • This discovery was important because he helped other scientists that the laws of physics are the same for all non-accelerating observers.