Ancient Astronomers

  • 240 BCE

    Eratosthenes

    Eratosthenes is credited with measuring the Earth’s diameter. He did so by measuring a shadow cast by a column.
  • 150

    Claudius Ptolemy

    He is famous for his geocentric model of the universe. While he is incorrect, it helped lead to the heliocentric discovery.
  • 1515

    Nicolaus Copernicus

    He first came up with the idea that the Sun is in the center of the solar system. We proved that the heliocentric model is correct.
  • Tycho Brahe

    Brahe discovered the geo-heliocentric model (also known as the Tychonic system). This is important because it led to the discovery to the correct model of the solar system (heliocentric).
  • Johannes Kepler

    Kepler’s Laws are named after him because he discovered that planets move in ellipses, and that they slow down based on how far from the sun a planet is in orbit.
  • Sir Isaac Newton

    Newton discovered the laws of gravity. These are important basics that explain a lot of things, and help us to discover more.
  • Albert Einstein

    One of the greatest things Einstein is known for is the discovery of the Theory of Relativity. It is known as the building block for physics.