Our Ideas About Cosmology

  • 1543

    Nicolaus Copernicus

    Proposed a Sun-centred Universe.
  • Tyco Brahe

    Worked on developing astronomical instruments and in measuring and fixing the positions of stars.
  • Johannes Kepler

    Discovered three major laws of planetary motion, the planets move in elliptical orbits with the Sun at one focus; the time necessary to traverse any arc of a planetary orbit is proportional to the area of the sector between the central body and that arc; and there is an exact relationship between the squares squares of the planet's periodic times and the cubes of the radii of their orbits.
  • Isaac Newton

    He discovered the laws of gravity and motion, he invented calculus and helped shape our rational world view.
  • Pierre-simon Laplace

    Laplace announced the invariability of planetary mean motions, allowing for the first and most important step in establishing the stability of the solar system.
  • William Herschel

    Discovered Uranus as the seventh planet.
  • Percival Lowell

    Initiated the search that ended in the discovery of Pluto
  • Williem de Sitter

  • Henrietta Leavitt

    Helped turn the sky into a three-dimensional map allowing astronomers to sove the distance of various things.
  • Albert Einstein

    Einstein presented his theory of relativity, proposing that gravity is a curved field in the space-time continuum created by the existence of mass.
  • Harlow Shapley

    Realised that the Milky Way Galaxy was much larger than previously believed, also discovered that the Sun lies near the central plane of the Milky Way Galaxy, but not at the exact centre.
  • Edwin Hubble

    Hubble discovered that there was a plethora of galaxies beyond the boundary of our Milky Way.
  • Georges Lemaître

    Georges Lemaître was the first scientist to figure out the basics of how our universe was created, his ideas led to the creation of the "Big Bang" theory.
  • Fred Hoyle

    Hoyle proved that the great majority of natural elements in the periodic table were made inside stars and distributed through space by supernova explosions.
  • Arno Penzias and Robert Wilson

    They discovered cosmic radiation appeared to become weaker as wavelengths of the radiation became shorter. When they studied cosmic radiation in 1964, they discovered that microwaves with a wavelength of about 7 centimetres were stronger than expected.