Ancient Astronomers Timeline

  • 240 BCE

    Eratosthenes Measurement of Earth

    Eratosthenes Measurement of Earth
    The measurement of Earth was important becasue it supported the belief that the Earth is round and provided a measurement for how big the Earth was.
  • 127

    Claudius Ptolemy's Star Catalog

    Claudius Ptolemy's Star Catalog
    This is an important discovery becasue it allowed astronomers to predict planetary positions and eclipses.
  • 1543

    Nicolaus Copernicus' Heliocentric Theory

    Nicolaus Copernicus' Heliocentric Theory
    This is important becasue he is the first astronomer to state that planets orbit the Sun.
  • 1572

    Tycho Brahe's New Star

    Tycho Brahe's New Star
    This was an important discovery becasue other scientists realized this was a supernova and was in fact not new.
  • Johannes Kepler's Laws of Planetary Motion

    Johannes Kepler's Laws of Planetary Motion
    This is an important discovery becasue it provided the first quantitative connection between planets.
  • Sir Isaac Newton's Laws of Motion

    Sir Isaac Newton's Laws of Motion
    These laws were important becasue they set the foundation for basic mechanics.
  • Albert Einstein's Theory of Relativity

    Albert Einstein's Theory of Relativity
    This theory is essential becasue it helps astronomers predict black holes, planetary orbits, etc in space.