5.8 Ancient Astronomers Timeline

By river26
  • Eratosthenes
    236 BCE

    Eratosthenes

    He measured the Earth's circumference mathematically using two surface points to make the calculation. He invented a system of longitude and latitude and made a map of the known world.
  • Claudius Ptolemy
    127

    Claudius Ptolemy

    Based on observations he made with his naked eye, Ptolemy saw the Universe as a set of nested, transparent spheres, with Earth in the center. He posited that the Moon, Mercury, Venus, and the Sun all revolved around Earth.
  • Nicholaus Copernicus
    1532

    Nicholaus Copernicus

    Copernicus was the one who proposed that the sun was stationary in the center of the universe and the earth revolved around it.
  • Tycho Brane

    Tycho Brane

    Brane is responsible for devising the most precise instruments available before the invention of the telescope for observing the heavens.
  • Johannes Kepler

    Johannes Kepler

    Kepler created the laws of planetary motion. His first law stated that planets move in elliptical paths around the Sun. He also discovered that planets move proportionally faster in their orbits when they are closer to the Sun; this became Kepler's Second Law.
  • Sir Isaac Newton

    Sir Isaac Newton

    Newton is best known for formulating gravitational theory which came from him watching an apple fall and asking why the apple fell straight down and not sideways or even upward.
  • Albert Einstein

    Albert Einstein

    Einstein thought that space and time were intertwined in an infinite "fabric", like an outstretched blanket. This eventually led to an explanation of the origin of the universe.