A Brief History of Human Astronomy

40,000 years BC - Human language begins
20,000 years BC - Agriculture: map seasons with sky
5,500 years BC - Writing developed
2,000 years BC - Systematic astronomy begins
1,500 years BC - First sundial
300 years BC   - Greeks catalog 45 constellations

170 years AD   - Ptolemy: earth-centered theory
400 years AD   - Dark Ages begin
800 years AD   - Arabs name stars, begin scientific astronomy
1054 years AD  - Crab Nebula Supernova
1540 years AD  - Copernicus: sun-centered solar system
1600 years AD  - Kepler: planetary orbits elliptical
1603 years AD  - Bayer publishes Uranometria

1610 years AD  - Galileo uses "spyglass" for astronomy
                 moon craters, sunspots, moons of Jupiter, 
                 stars in milky way
1670 years AD  - Newton: reflecting telescope
1675 years AD  - Roemer: speed of light from Jupiter's moons
1687 years AD  - Newton: unifies math and astronomy
1758 years AD  - Comet returns as Halley predicts
1781 years AD  - Herschel: discovers planet Uranus
                 Starts first telescopic survey of sky, 
               - Messier: catalog of nebulae
1810 years AD  - Fraunhofer: solar and stellar spectra
1846 years AD  - Many people discover planet Neptune 
1850 years AD  - Harvard: first astrophoto - the Moon
1859 years AD  - Webb: first amateur astronomy book

1906 years AD  - Henrietta Leavitt: observes Cephieds 
1910 years AD  - Parallax measurement of distance to stars
1916 years AD  - Einstein: General Theory of Relativity
1924 years AD  - Hubble: nebulae are remote galaxies
1928 years AD  - IAU establishes official 88 constellations
1930 years AD  - Tombaugh: discovery of Pluto
1931 years AD  - Hubble: expanding universe
1937 years AD  - Reber: first radio telescope
1938 years AD  - Bethe: stars glow with nuclear fusion
1940 years AD  - Big Bang Theory
1959 years AD  - NASA formed
1963 years AD  - Schmidt: Quasars are very remote
1969 years AD  - First humans on the moon
1979 years AD  - Voyagers start tour of outer solar system
1990 years AD  - Hubble Space Telescope launched
Today          - You study astronomy on the internet