Earth

2.5 Changing Timelines Kate Mills

  • 276 BCE

    Erastathones is Born

  • 236 BCE

    Erastathones Becomes Chief Librarian of Library of Alexandria

    During the time in this position, Erastathones not only invented latitude and longitude, but made a very accurate estimate of the Earth's circumference.
  • 194 BCE

    Erastathones Dies

  • 85

    Ptolemy is Born

    Ptolemy is Born
    Claudius Ptolemy is born in Alexandria, Egypt.
  • Period: 85 to 165

    Ptolemy's Lifetime

    Ptolemy synthesized the Greek knowledge of the known, geocentric universe. He was influenced by Aristotle to add to the geocentric theory. Based on what he was able to see with a naked eye, he believed the universe to be a set of nested, transparent spears which revolved around the Earth. He believed that past Saturn, there lay a giant sphere to which all of the stars were attached. Hipparchus' explanation of epicyles helped him explain the science and calculations behind the geocentric theory.
  • 165

    Ptolemy's Death

    Ptolemy passes away.
  • Feb 19, 1473

    Copernicus is Born

  • 1492

    Copernicus Attends Krakow University

    During this time, Copernicus studies math, Greek, and Islamic astronomy, with expenses being paid for by his wealthy uncle. At Krakow, Copernicus begins to question the validity of Aristotle and Ptolemy's view of the geocentric Universe and became increasingly aware of the contradictions between the planets being concentric spheres yet having eccentric orbits.
  • 1501

    Copernicus Attends Padau University

    While attending Padau University, Copernicus develops some evidence for a new system of cosmology that differs from the geocentric theory,
  • 1510

    Copernicus Measures the Universe

    When working as canon of a church, Copernicus uses the tower to make measurements on the stars. To make measurements, he would measure the angles, altitudes, and distances of stars and planets. This further deviated his theory of the universe from the geocentric theory.
  • 1514

    Copernicus Shares his Heliocentric Theory

    By 1514, Copernicus had written a short report (called the Little Commentary) on his heliocentric theory of the universe, sharing this viewpoint with some of his scientific peers.
  • 1532

    Copernicus Completes his Scientific Findings

    After 16 arduous years of measurements, Copernicus completes his detailed astronomical manuscript on his heliocentric theory. This further demonstrates his loyalty to the theory and deviance from the norms of the past.
  • 1541

    Copernicus Publishes His Heliocentric Theory

    After many years, Copernicus publishes his book "De Revolutionibus Orbium Celestium," which fully explained his measurements and reasons for believing in the heliocentric theory. With this, his thoughts could be shared with the world, influencing the geocentric theory to be further questioned and eventually disproved.
  • May 24, 1543

    Copernicus Dies

  • Feb 15, 1564

    Galileo's Birth

    Galileo's Birth
    Galileo Galilei is born in Pisa, Italy.
  • Galileo Finds Interest In Astronomy

    Galileo Finds Interest In Astronomy
    While observing the tides, Galileo recognizes that they do not line up with the geocentric theory. This lead to him beginning to support the heliocentric theory.
  • Galileo Reading about the Heliocentric Theory

    Galileo reads a book by Johannes Kepler that supports the heliocentric theory, to which Galileo responded by writing Kepler a letter stating that he agreed with the theory but was too afraid to express it to the scientific community.
  • Galileo Sees a Supernova

    While observing the sky, Galileo witnesses a supernova, which challenges Aristotle's claims that no change would every occur in the heavens.
  • Galileo Sees Jupiter's Moons

    Galileo saw all four of the moons that orbited Jupiter, disproving the geocentric theory that everything orbited around Earth.
  • Galileo Writes The Starry Messenger

    Galileo Writes The Starry Messenger
    Galileo wrote a book which published his findings surrounding the heliocentric theory.
  • Galileo Publishes Letters on Sunspots

    Galileo publishes his findings revolving on the idea that the dark spots on the sun are the result of magnetic activity.
  • Galileo's Book

    Galileo's work covered the principles of the geocentric and heliocentric theories in relation to their strong and weak points. It was met with high distaste.
  • Galileo's Death

    Galileo's Death
    Galileo died at the age of 77.
  • Isaac Newton is Born

  • Newton Attends Elementary School

    While in elementary school, Newton spends his time making numerous scientific contraptions instead of socializing with other kids. This demonstrates his passion for science from an extremely young age.
  • Newton Attends Cambridge University

    In pursuit of a mathematics degree, Newton attends Cambridge University, where his deepened understanding of math allows him to link science and math together.
  • Newton Makes Initial Discoveries

    Newton discovers and proves that white light is composed of all colors. He also begins to discover the law of universal gravitation.
  • Newton Publishes his Revolutionary Book, Gathers Further Evidence for Heliocentric Theory

    Newton publishes the "Mathematical Principles of Natural Philosphy," which covered the three laws of motion, expanded on Kepler's Laws of Motion, and stated the Law of Universal Gravitation. During this time, Newton observed planetary motion through a telescope of his own design, furthering his testimonies for the heliocentric theory.
  • Newton Dies

  • Dmitri Mendeleev is Born

  • Mendeleev Begins Education

    After the family factory burned down, Mendeleev's mother traveled to St. Petersburg in order to get him an education, which she succeeded in doing.
  • Mendeleev Returns to Russia And Teaches

    Mendeleev returned from his studies and began to teach chemistry at the technical insitute of St petersburg. He also wrote the first textbook regarding explanations and background for organic chemistry.
  • Mendeleev Began Writing Principles of Chemistry

    He began to write a book that would be able to explain and organize the elements.
  • Marie Curie is Born

    Marie Curie is born in Warsaw, Poland
  • Mendeelev Writes About Inorganic Chemistry

    After writing his book about organic chemistry, Mendeleev decided to write one for Inorganic chemistry, which became the standard text in the field.
  • Mendeleev Devises the First Periodic Table

    Mendeleev made flashcards of each elements and in a dream, saw a vision where the cards all arranged themselves into a table, which he named the periodic table of elements. He learned about the Periodic Law which relates to atomic mass.
  • Gallium is Discovered

    The discovery of gallium fit perfectly with Mendeleev's table, proving its accuracy.
  • Alfred Wegener Born

  • Curie Graduates Highschool

    At age 15, Curie graduates highschool with a love of science since her father had surrounded her with scientific instruments from a young age.
  • Curie Graduates from Sorbonne

    Curie is the first ever woman to graduate with a degree in physics at Sorbonne.
  • Marie Marries Pierre Curie

    Marie marries Pierre Curie, who was also a scientist, furthering her lifelong passion for science.
  • Curie Discovers Radium

    After years of research and speculations, Curie discovers the element radium, and along with it the concept of radioactivity.
  • Curie Clearly Sees Radium

    After working strenuously to separate radium from other substances, Marie succeeds and is able to see radioactivity clearly for the first time, allowing her to develop a theory on radioactivity. This theory allowed scientists to further understand the structure of an atom, in turn allowing them to understand the structure of matter, in turn allowing them to evaluate the structure of the universe.
  • Curie Wins Nobel Prize

    Curie gets a doctors degree in physics and receives a Nobel Prize for her discovery of radioactivity.
  • Wegner Recieves a PhD in Astronomy

  • Harry Hess is Born

  • Mendeleev Dies

  • Wegener Notices South America Border Fits with Africa

    Wegener realizes how the borders of these two continents fit together and theorizes that they might have been joined.
  • Wegener Publishes His Book

    Wegener publishes the "Origin of Continents and Oceans" which provides the first explanation for the land mass called pangea.
  • Wegener Accepts Professorship

    Wegener accepted a professorship of meteorology and geophysics
    at the University of Graz in Austria.
  • Wegener Dies

  • Curie Dies

  • Hess Publishes Theory of Ocean Spreading

  • Hess Dies of a Heart Attack