History of Astronomy

  • 322 BCE

    Aristotle

    Aristotle
    Believed that earth was round, was the center of the universe, and that the stars, planets, the sun, and the moon revolve around earth.
  • 120 BCE

    Hipparchus

    Hipparchus
    Calculated the length of the year within 6 1/2 minutes, compiled the first star catalog, and created the early form of triganometry
  • 117

    Ptolemy

    Ptolemy
    He believed the earth was round and he called his idea the geocentric theory.
  • May 21, 1542

    Copernicus

    Copernicus
    After everyone believed that the earth was the center of the universe Nicolaus Copernicus proposed that the planets actually revolve around the sun.
  • Dec 27, 1571

    Johannes Kepler

    Johannes Kepler
    Kepler's laws are that all of the planets move in orbit of the sun, a radius vector joining any planet to the Sun sweeps out equal areas in equal lengths of time, and the square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.
  • Tycho Brahe

    Tycho Brahe
    Helped overturn favor to the heliocentric belief of astronomy.
  • Hans Lippershey

    Hans Lippershey
    Created the first telescope.
  • Giovanni Cassini

    Giovanni Cassini
    Discovered the difference in the darkness in Saturn's rings, the spaces between them, and Saturn's 4 moons
  • Galileo

    Galileo
    Used his newly invented telescope to look at moons revolving around Jupiter which strengthened the heliocentric theory.
  • Sir Isaac Newton

    Sir Isaac Newton
    States that a particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. Reflecting telescope. 3 laws of motion.
  • William Herschel

    William Herschel
    The founder of sidereal astronomy for the systematic observation of the heavens. Discovered Uranus. Determined the temperature of the different colors of sunlight passed through a prism.
  • Percival Lowell

    Percival Lowell
    Fueled speculation that there were canals on Mars. Discovered Pluto
  • Ejnar Hertzsprung

    Ejnar Hertzsprung
    Together with Henry Norris Russell, he developed the Hertzsprung–Russell diagram that plotted the absolute magnitude of stars against their color.
  • Albert Einstein

    Albert Einstein
    Equation that helped explain special relativity – E = mc2 – and gravitation.
  • Edwin Hubble

    Edwin Hubble
    Played a crucial role in establishing the fields of extragalactic astronomy and observational. Big Bang Theory. Universe moving away from eachother.
  • Karl Jansky

    Karl Jansky
    In August 1931 first discovered radio waves emanating from the Milky Way. He is considered one of the founding figures of radio astronomy.
  • John Glenn

    John Glenn
    He was an aviator, engineer, astronaut, and United States Senator from Ohio in the marine corps. He was the first american to orbit space when he orbited earth 3 times. 1962.
  • Neil Armstrong

    Neil Armstrong
    He was an American astronaut, engineer, and the first person to walk on the Moon. Began working at NASA after being a naval aviator. 1969- Gemini 8 and Apollo 11.
  • Yuri Gagarin

    Yuri Gagarin
    He was a soviet cosmonaut and pilot. He was the first human to go into outer space when his Vostok spacecraft orbited earth. 1961
  • Sputnik

    Sputnik
    Sputnik 1 was the first artificial satellite that the soviet union sent out into space. It is 23 inches in diameter and has orbited earth 1440 times.
  • Period: to

    Apollo Missions

    The Apollo Program was a series of missions that involved many spacecrafts that took humans to the moon and back.
  • First Space Shuttle flight- Columbia

    First Space Shuttle flight- Columbia
    Launch like a rocket and lands like a plane.
  • Mars Pathfinder Expedition

    Mars Pathfinder Expedition