Human Accomplishments – Astronomy

Central Events in Astronomy

Murray, C.A. (2003) Human accomplishment the pursuit of excellence in the Arts and Sciences, 800 B.C. to 1950. HarperCollins Publishers.
Year	Country	Event
500 BCE	Greece	Pythagoras of Samos discovers that the morning and the evening star are the same.
165 BCE	China	Chinese astronomers describe sunspots.
134 BCE	Alexandria	Hipparchus invents a system of magnitude for measuring the brightness of stars, still the basis of the modern system.
134 BCE	Alexandria	Hipparchus prepares the first accurate, systematic star catalog and sky map.
130 BCE	Alexandria	Hipparchus calculates the first reasonably accurate estimate of the distance to the moon.
140	Alexandria	Ptolemy’s Almagest constructs a model of a geocentric solar system that accurately predicts the movements of the planets.
1514	Poland	Nicolaus Copernicus’s Commentarioliis is the first statement of the heliocentric theory. It culminates in the publication of De Revolutionibus Orbium Coelestium in 1543.
1572	Denmark	Tycho Brahe records the first European observation of a supernova, discrediting the Aristotelian system of a fixed sphere of stars.
1604	Germany	Johannes Kepler observes a second nova, confirming Brahe’s discovery.
1608	Netherlands	Hans Lippershey and Zacharias Jansen independently invent a crude telescope.
1609	Germany	Johannes Kepler’s Astronomici Nova contains the first statement of Kepler’s first two laws of planetary motion.
1609	Italy	Galileo conducts the first telescopic observations of the night sky, transforming the nature of astronomical investigation.
1609	Italy	Galileo constructs the first working telescope, 9x magnification initially, improved to 30x by the end of the year.
1610	Italy	Galileo discovers four moons of Jupiter and infers that the earth is not the center of all motion. (Simon Marius makes a disputed claim to the same discovery.)
1611	Italy, Germany	Galileo, Christoph Scheiner, and Girolamo Fabrici independently demonstrate that sunspots are part of the sun and revolve with it.
1612	Germany	Simon Marius publishes the first systematic description of the Andromeda Nebula.
1631	France	Pierre Gassendi describes the transit of Mercury.
1655	Netherlands	Christiaan Huygens discovers the rings of Saturn. He also discovers the first moon of Saturn, Titan, another in a series of discoveries of planetary satellites, asteroids, and other celestial bodies that continues to the present. Several of these discoveries are cited in all of the sources and are included separately in the full inventory, but only a few of special significance are included in this roster.
1668	England	Isaac Newton invents the first working reflecting telescope.
1705	England	Edmond Halley's A Synopsis of the Astronomy of Comets includes calculation of the orbits of comets and the first prediction of a comets return.
1718	England	Edmond Halley discovers stellar motion (proper movement of stars).
1755	Germany	Immanuel Kant’s Allgemeine Naturgeschichte und Theorie Des Himmels hypothesizes that the solar system is part of a huge, lens-shaped collection of stars, that other such “island universes” exist, and proposes a theory of the evolution of the universe in which particles conglomerated to form heavenly bodies.
1761	Russia	Mikhail Lomonosov infers the existence of a Venusian atmosphere.
1781	England	William Herschel discovers Uranus.
1782	England	John Goodricke is the first to observe an eclipsing variable star.
1785	England	William Herschel's On the Construction of the Heavens is the first quantitative analysis of the Milky Way’s shape.
1794	Germany	Ernst Chladni and Heinrich Olbers defend the extraterrestrial origin of meteorites and offer a scientific explanation of them.
1802	Germany	Heinrich Olbers argues that asteroids are fragments of an exploded planet.
1803	France	Jean-Baptiste Biot discovers empirical verification of meteorites as extraterrestial objects.
1814	Germany	Joseph von Fraunhofer discovers that spectral lines observed in light reflected from the planets are shared, while light from stars contains differing lines, leading to the development of astronomical spectroscopy.
1838	Scotland, Germany	Thomas Henderson and Friedrich Bessel are the first to measure a star’s heliocentric parallax, permitting an estimate of stellar distance.
1843	Germany	Samuel Schwabe discovers the sunspot cycle, founding the modern study of solar physics.
1844	Germany	Friedrich Bessel infers an unseen “dark companion” star of Sirius, the first known binary star.
1845	Ireland	William Parsons discovers spiral nebulae.
1846	England, France, Germany	John Couch and Urbain le Verrier predict the existence and orbit of Neptune, which is then observed by Johann Galle.
1859	Germany	Gustav Kirchhoff and Robert Bunsen conduct the first analysis of the chemical composition of the stars, the first step in understanding the evolution of the stars.
1905	Denmark	Ejnar Hertzsprung defines a scale for color and stellar luminosity, used to establish stellar magnitudes.
1908	USA	George Hale discovers that sunspots exhibit the Zeeman effect, implying that they are subject to an electromagnetic field.
1912	USA	Henrietta Leavitt devises a method for determining the luminosity of a Cepheid variable from its period, thereby enabling a determination of its distance and measurement of other extragalactic distances.
1914	USA	Henry Russell’s “Relations Between the Spectra and Other Characteristics of the Stars” develops a theory of stellar evolution.
1918	USA	Harlow Shapley determines the center of the galaxy, providing a correct picture of our own galaxy plus the first accurate estimate of its size.
1920	USA	Albert Michelson calculates the first measurement of stellar diameter, for the star Betelgeuse.
1924	USA	Edwin Hubble determines that Andromeda is a galaxy, revolutionizing the understanding of the universe’s size and structure.
1927	Belgium	Georges Lemaitre introduces the idea of the cosmic egg, the forerunner of the Big Bang theory.
1929	USA	Edwin Hubble discovers Hubble’s Law, introducing the concept of an expanding universe.
1930	France	Bernard Lyot invents the coronagraph, permitting extended observations of the sun’s coronal atmosphere.
1930	Germany	Bernhard Schmidt invents the Schmidt camera and telescope, permitting wide-angle views with little distortion.
1930	USA	Clyde Tombaugh discovers Pluto based on analysis of the perturbations in the orbits of the outer planets caused by an unknown body.
1932	USA	Karl Jansky detects radio waves from space, founding radio astronomy.
1934	Switzerland, USA	Fred Zwicky and Walter Baade predict the existence of neutron stars.
1934	Switzerland, USA	Fritz Zwicky and Walter Baade discover the difference between novae and supernovae.
1937	USA	Grote Reber invents the radio telescope.
1938	Germany, USA	Hans Bethe and Carl Weizsacker present a detailed case for nuclear fusion as the source of a stars energy.
1942	USA	Grote Reber prepares the first radio map of the universe, locating individual radio sources.
1944	Germany	Carl Weizsacker formulates the planetesimal hypothesis to explain the origin of the solar system.
1948	USA	George Gamow and Ralph Asher develop the Big Bang theory, employing Hans Bethe s results from thermonuclear reactions.
1949	USA	Fred Whipple discovers the “dirty snowball” composition of comets.

A culture that no longer recognizes achievement or thinks in terms of greatness is on course to spiral down into stagnation and senescence.