History of Astronomy

  • Aristotle
    322 BCE

    Aristotle

    Aristotle was an Ancient Greek Philosopher. He was the founder of a school Lyceum in Athens, Greece.
  • Ptolemy
    168

    Ptolemy

    Latin in full Claudius Ptolemaeus. Egyptian, astronomer, mathematician, and geographer of Greek descent.
  • Copernicus
    1543

    Copernicus

    Polish astronomer who proposed that the planets have the sun as the fixed point to which their motions are to be referred. Wrote a manuscript called the Commentariolus.
  • Tycho Brahe

    Tycho Brahe

    Developing astronomical instruments. Fixing positions of stars paved the way for future discoveries.
  • Hans Lippershey

    Hans Lippershey

    Lippershey applied to States General of Netherlands for 30-year patent for instrument. States General granted Lippershey 900 florins for instrument.
  • Johannes Kepler

    Johannes Kepler

    Johannes Kepler was a German astronomer who discovered three major laws of planetary motion. Planets move in orbits, time, periodic times.
  • Galileo

    Galileo

    Italian natural philosopher, astronomer, and mathematician. Made fundamental contributions to sciences of motion, astronomy, and strength of materials.
  • Giovanni Cassini

    Giovanni Cassini

    Italian-born French astronomer. Early studies were principally observations of the Sun.
  • Sir Isaac Newton

    Sir Isaac Newton

    English physicist and mathematician. Original discoverer of the infinitesimal calculus.
  • William Herschel

    William Herschel

    Founder of sidereal astronomy. Discovered the planet Uranus
  • Percival Lowell

    Percival Lowell

    Discovered the planet Pluto. Was counselor and foreign secretary to Korean Special Mission to US.
  • Karl Jansky

    Karl Jansky

    American engineer whose discovery of radio waves from an extraterrestrial source inaugurated the development of radio astronomy. Joined the Bell Telephone Laboratories in New Jersey.
  • Edwin Hubble

    Edwin Hubble

    American astronomer who played a crucial role in establishing the field of extragalactic astronomy. Regarded as the leading observational cosmologist of the 20th century.
  • Albert Einstein

    Albert Einstein

    Developed the special and general theories of relativity and won the Nobel Prize for Physics in 1921. Considered the most influential physicist of the 20th century.
  • Sputnik

    Sputnik

    The first artificial Earth satellite. Soviet Union launched it into an elliptical low Earth orbit on 4 October 1957, orbiting for three weeks before batteries died, then silently for two more months before falling back into the atmosphere.
  • John Glenn

    John Glenn

    The first U.S. astronaut to orbit Earth. He completed three orbits in 1962. He joined the U.S. Naval Reserve in 1942.
  • Ejnar Hertzsprung

    Ejnar Hertzsprung

    Had no formal education in astronomy. Appointed assistant director of the university observatory at Leiden, Neth., in 1919 and became director in 1935.
  • Yuri Gagarin

    Yuri Gagarin

    He was a Soviet pilot and cosmonaut. He became the first human to journey into outer space when his Vostok spacecraft completed one orbit of the Earth on 12 April 1961.

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