Ancient Astronomers Timeline

By jwalk22
  • Period: 276 BCE to 195 BCE

    Eratosthenes

    He was known for using the sun to measure the size of the round earth. He concluded that his measurement was 24,660 miles. Though this was not accurate, he was still close, as he was only 211 miles off. This was important because it was the first ever measurement to take place.
  • Period: 90 to 168

    Claudius Ptolemy

    He developed the Geocentric Theory, the belief that the Earth is at the center of our System. Though his theory was incorrect, he was still able to merge what he believed of the stars’ movements with mathematics. Even though he was wrong, many people still accepted his view for many centuries.
  • Period: 1473 to 1543

    Nicolas Copernicus

    He developed the Heliocentric System which stated that the sun is at the center of our system. Though he wasn’t the first to come up with this idea, he was the one who brought it to life in the Renaissance Era. He backed up his idea through observations of the movements of the planets. This is also significant because this model is still accepted today as accurate.
  • Period: 1546 to

    Tycho Brahe

    He spent his time building vast instruments to set accurate sights on the stars. He used clocks and timekeepers, until he eventually reached his goal which was measuring to one minute of arc. This was important, because he was trying to confirm his own picture of the Universe. Even if it happened to be slightly incorrect.
  • Period: 1571 to

    Johannes Kepler

    He developed the three laws of planetary motion. This was important as it helped Isaac Newton establish universal gravitation.
  • Period: to

    Sir Isaac Newton

    He is most famous for his work on forces, specifically gravity, which led to what is now called Newton’s Laws, three laws that describe the motion of force between objects. This is important, as it permanently altered the field of science. His discovery of Newton’s Laws led to the foundation of classical mechanics, which is known to be one of the main branches of physics.
  • Period: to

    Albert Einstein

    He proposed a new way of looking at the Universe, that being that the laws of physics are the same throughout the universe. This means that the speed of light in a vacuum is constant, and that space and time are connected in an entity referred to as space-time. This is important, because like Newton, his ideas altered history. His proposal of the universe went beyond our current understanding at that time.