Famous Astronomers and Astrophysicists

Famous Astronomers and Astrophysicists Famous Astronomers
and Astrophysicists

Alphabetical

Classical Period
Nicolaus Copernicus	1473-1543 Polish	developed a simple heliocentric model of the solar system that explained planetary retrograde motion and overturned Greek astronomy
Tycho Brahe	1546-1601 Danish	observed a supernova now known as “Tycho's supernova”; made the most precise observations of stellar and planetary positions then known
Galileo Galilei	1564-1642 Italian	performed fundamental observations, experiments, and mathematical analyses in astronomy and physics; discovered mountains and craters on the moon, the phases of Venus, and the four largest satellites of Jupiter: Io, Europa, Callisto, and Ganymede
Johannes Kepler	1571-1630 German	established the most exact astronomical tables then known; established the three laws of planetary motion
John Babtist Riccioli	1598-1671 Italian	made telescopic lunar studies and published detailed lunar maps in which he introduced much nomenclature for lunar objects; discovered the first double star (Mizar)
Giovanni Cassini	1625-1712 Italian-born French	measured rotational periods of Jupiter and Mars; discovered four satellites of Saturn and the gap in Saturn's rings now known as “Cassini's division”
Christiaan Huygens	1629-1695 Dutch	discovered Saturn's first satellite, Titan, and the true shape of Saturn's rings
Sir Isaac Newton	1643-1727 English	developed theories of gravitation and mechanics, and invented differential calculus
Edmond Halley	1656-1742 British	used his theory of cometary orbits to predict that the comet of 1682 (later named “Halley's comet”) was periodic
Charles Messier	1730-1817 French	discovered 19 comets, 13 being original and 6 independent co-discoveries; compiled a famous catalog of deep-sky objects
Joseph-Louis Lagrange	1736-1813 French	developed new methods of analytical mechanics; made many theoretical contributions to astronomy, improving our understanding of lunar motion and the perturbing effects of planets on cometary orbits; found solution to 3-body problem showing there could be two points (now called Lagrange points) in orbit of Jupiter where minor planets could stay almost indefinitely - the Trojan group of asteroids were later discovered at these positions
William Herschel	1738-1822 British	discovered Uranus and its two brightest moons, Titania and Oberon; discovered Saturn's moons, Mimas and Enceladus; discovered the ice caps of Mars, several asteroids and binary stars; cataloged 2,500 deep sky objects
Giuseppe Piazzi	1746-1826 Italian	discovered the largest asteroid, Ceres; accurately measured positions of many stars, resulting in a star catalog
Johann Bode	1747-1826 German	popularized a relationship giving planetary distances from the Sun, which became known as “Bode's law”; predicted an undiscovered planet between Mars and Jupiter, where the asteroids were later found
Pierre-Simon Laplace	1749-1827 French	made important mathematical contributions to differential equations; promoted the solar nebula hypothesis for the origin of the solar system
Caroline Herschel	1750-1848 British	discovered several comets and was first woman to discover a comet
Heinrich Wilhelm Olbers	1758-1840 German	invented first successful method for calculating cometary orbits; discovered several comets, including the comet of 1815, now called Olber's comet; discovered the asteroids Pallas and Vesta; posed the famous Olber's paradox: “Why is the night sky dark?”
Friedrich Bessel	1784-1846 Prussian	first to measure distance to the star 61 Cygni; proposed that Sirius has an unseen companion; worked out the mathematical analysis of what are now known as Bessel functions
Joseph von Fraunhofer	1787-1826 German	made detailed wavelength measurements of hundreds of lines in the solar spectrum; designed an achromatic objective lens
Johann Franz Encke	1791-1865 German	discovered the first short-period comet, now called Encke's comet
Friedrich von Struve	1793-1864 German-born Russian	founded the study of double stars; published catalog of over 3000 binary stars; first to measure distance to the star Vega
Wilhelm Beer	1797-1850 German	prepared and published maps of the Moon and Mars
Thomas Henderson	1798-1844 Scottish	first to measure distance to a star (Alpha Centauri)
William Lassell	1799-1880 British	discovered Triton, the largest satellite of Neptune
Sir George Airy	1801-1892 British	improved orbital theory of Venus and the Moon; studied interference fringes in optics; made a mathematical study of the rainbow
Urbain Le Verrier	1811-1877 French	accurately predicted the position of Neptune, which led to its discovery
Johann Gottfried Galle	1812-1910 German	first person to observe Neptune, based on calculations by French mathematician, Urbain Le Verrier; however, Neptune's discovery is usually credited to Le Verrier and English astronomer, John Crouch Adams, who first predicted its position
Anders Ångström	1814-1874 Swedish	discovered hydrogen in the solar spectrum; source of the Angstrom unit
Daniel Kirkwood	1814-1895 American	discovered the “Kirkwood gaps” in the orbits of the asteroids between Mars and Jupiter; explained the gaps in Saturn's rings
William Huggins	1824-1910 British	first to show that some nebulae, including the great nebula in Orion, have pure emission spectra and thus must be gaseous
Sir Joseph Lockyer	1836-1920 British	discovered in the solar spectrum a previously unknown element that he named helium
Henry Draper	1837-1882 American	made first photograph of a stellar spectrum (that of Vega); later photographed spectra of over a hundred stars and published them in a catalog; studied spectrum of Orion Nebula, which he showed was a dust cloud
Edward Charles Pickering	1846-1919 American	discovered the first spectroscopic binary star, Mizar
Jacobus Cornelius Kapteyn	1851-1922 Dutch	discovered that the proper motions of stars were not random, but stars could be divided into two streams moving in opposite directions, representing the rotation of our galaxy
Edward Barnard	1857-1923 American	discovered eight comets and Almathea, the fifth moon of Jupiter; also discovered star with largest proper motion, now called Barnard's star
Nobel Laureates
Hannes Alvén	1908-1995 Swedish	developed the theory of magnetohydrodynamics
Subramanyan Chandrasekhar	1910-1995 Indian-born American	made important theoretical contributions concerning the structure and evolution of stars, especially white dwarfs
William Fowler	1911-1995 American	carried out extensive experimental studies of nuclear reactions of astrophysical significance; developed, with others, a complete theory of the formation of chemical elements in the universe
Antony Hewish	1924- British	led the research group that discovered the first pulsar
Arno A. Penzias	1933- German-born American	co-discovered the cosmic microwave background radiation
Robert W. Wilson	1936- American	co-discovered the cosmic microwave background radiation
Joseph H. Taylor, Jr.	1941- American	co-discovered the first binary pulsar
Russell Alan Hulse	1950- American	co-discovered the first binary pulsar
Others
Annie Jump Cannon	1863-1941 American	classified spectra of many thousands of stars; published catalogs of variable stars (including 300 she discovered)
Maximilian Wolf	1863-1932 German	discovered hundreds of asteroids using photography
George E. Hale	1868-1938 American	revolutionized spectral observations by inventing and using the spectroheliograph; discovered magnetic fields in sunspots; first astronomer to be officially called an astrophysicist; founded the Yerkes, Mt. Wilson, and Palomar Observatories
Henrietta Swan Levitt	1868-1921 American	discovered the period-luminosity relation for Cepheid variables
Willem de Sitter	1872-1934 Dutch	studied the astronomical consequences of Einstein's theory of general relativity; deduced that a near-empty universe would expand
Ejnar Hertzsprung	1873-1967 Danish	invented the color-magnitude diagram; by studying star clusters, independently discovered the relationship between absolute magnitude and spectral types of stars; a plot of this relationship is now called a Hertzsprung-Russell diagram (or H-R diagram); determined distance to the Small Magellanic Cloud
Karl Schwarzchild	1873-1916 German	first to give an exact solution of Einstein's equations of general relativity, giving an understanding of the geometry of space near a point mass; also made the first study of black holes
Kiyotsugu Hirayama	1874-1943 Japanese	discovered the existence of groups of asteroids with similar orbital elements. He hypothesized that the asteroids in these families (now called Hirayama families) were physically related
Vesto M. Slipher	1875-1969 American	first to measure the radial velocity of the Andromeda galaxy
Walter Sydney Adams	1876-1956 American	identified Sirius B as the first white dwarf star known
Henry Norris Russell	1877-1957 American	used photographic methods to measure stellar parallaxes, leading to the discovery of the relationship between absolute magnitude and spectral types of stars; a plot of this relationship is now called a Hertzsprung-Russell diagram (or H-R diagram)
Bernhard Schmidt	1879-1935 Swedish-born German	invented and constructed the first Schmidt reflecting telescope using a corrector plate he devised to eliminate aberration of the image
Arthur S. Eddington	1882-1944 British	first to confirm Einstein's prediction that light will bend near a star; discovered the mass-luminosity relation for stars; theoretically explained the pulsation of Cepheid variables
Harlow Shapley	1885-1972 American	discovered the size of our galaxy and the direction of its center by studying the distribution of globular clusters; determined the orbits of many eclipsing binary stars
Edwin Hubble	1889-1953 American	first to measure distance to the Andromeda nebula, establishing it to be a separate galaxy; later measured distances to other galaxies and discovered that they recede at a rate proportional to their distance (Hubble's law)
Walter Baade	1893-1960 German-born American	discovered the asteroids Hidalgo and Icarus; established two different stellar classes: the younger, hotter “Population I” and the older, cooler “Population II”
Georges-Henri Lemaitre	1894-1966 Belgian	advanced idea that the Universe originated as a small, dense “cosmic egg” that exploded and set its expansion into motion
Rudolph Minkowski	1895-1976 German	divided supernovae into Types I and II; optically identified many of the early radio sources
Bernard-Ferdinand Lyot	1897-1952 French	invented the coronagraph
Otto Struve	1897-1963 Russian-born American	made detailed spectroscopic studies of close binary stars; discovered interstellar matter (H II regions)
Fritz Zwicky	1898-1974 Swiss-American	observed Coma cluster of galaxies and determined that most of the cluster must be “dark matter”; proposed existence of and then observed dwarf galaxies; proposed existence of supernovas (a term he coined) and that their collapse might lead to neutron stars; anticipated discovery of quasars by proposing that compact blue galaxies might be mistaken for stars; anticipated that dark matter could be studied by observing galaxies that acted as gravitational lenses
Jan Hendrik Oort	1900-1992 Dutch	calculated distance to center of galaxy; determined period for sun to complete one revolution of Milky Way; calculated the mass of the Milky Way; proposed existence of huge spherical cloud of icy comets (the Oort cloud) left behind from formation of the solar system
Cecelia Payne-Gaposchkin	1900-1979 English	discovered that stars are composed primarily of hydrogren, with helium the second-most abundant element
George Gamow	1904-1968 Russian-born American	first suggested hydrogen fusion as source of solar energy
Karl G. Jansky	1905-1950 American	discovered radio waves from space, thereby pioneering the birth of radio astronomy
Gerard P. Kuiper	1905-1973 Dutch-born American	discovered Miranda, the fifth satellite of Uranus; discovered Nereid, the second satellite of Neptune; discovered the atmosphere of Titan, Saturn's largest satellite; his spectroscopic studies of Uranus and Neptune led to discovery of comet-like debris at the edge of the solar system, now called “Kuiper's belt”
Bruno B. Rossi	1905-1993 Italian	pioneer of x-ray astronomy and space plasma physics; participated in discovery of the first known x-ray source outside the solar system (Scorpius X-1)
Bart Jan Bok	1906-1983 Dutch	suggested that small dark globules of interstellar gas and dusk (now called Bok globules) are collapsing to form new stars
Clyde Tombaugh	1906-1997 American	discovered the planet Pluto
Fred Whipple	1906-2004 American	proposed the “dirty snowball” model of cometary structure
Viktor Ambartsumian	1908-1996 Soviet	one of the founders of theoretical astrophysics; first to suggest that T Tauri stars are very young and that nearby stellar associations are expanding
Grote Reber	1911-2002 American	built the first radio telescope (a parabolic reflector 31 feet in diameter), thereby becoming the first radio astronomer
Carl K. Seyfert	1911-1960 American	discovered the first active galaxy, part of a group now called Seyfert galaxies
John A. Wheeler	1911-2008 American	made theoretical contributions to understanding of quantum gravity; coined the term “black hole”; introduced the concept of “spacetime foam”
Karl F. von Weizsäcker	1912-2005 German	contributed to the development of the model nebular theory for the formation of the solar system; proposed (with Hans Bethe) the proton-proton reaction as the thermonuclear energy source for the sun
James A. Van Allen	1914-2006 American	a space scientist best known for discovering the Earth's magnetosphere
Sir Fred Hoyle	1915-2001 British	proponent of the steady-state model of the universe; well-known author of science fiction; proposed that earliest forms of life were carried through space on comets and that these primitive forms of life found their way to Earth; derisively coined the term “Big Bang” for a cosmic theory with which he did not agree
Robert H. Dicke	1916-1997 American	proposed that radiation near 1-cm wavelength is left over from the hot Big Bang; invented the microwave radiometer, used to detect this radiation
George H. Herbig	1920-2013 American	independently discovered the Herbig-Haro objects, which are gas clouds associated with young stars
E. Margaret Burbidge	1919- British	performed observational research on the spectra of quasars and other peculiar galaxies; contributed to understanding of stellar nucleosynthesis
Thomas Gold	1920-2004 American	contributed to our understanding of cosmology, the nature of pulsars as rotating neutron stars, and the origin of planetary hydrocarbons
Chushiro Hayashi	1920-2010 Japanese	discovered the pattern followed by pre-main-sequence stars on H-R diagrams (now called the Hayashi track); discovered the maximum radius for a star of a given mass (the Hayashi limit); made significant contributions to our understanding of Big Bang nucleosynthesis
Edwin E. Salpeter	1924-2008 Austrian-born American	explained how the triple-alpha reaction could make carbon from helium in stars; worked on atomic theory and quantum electrodynamics; co-developed the Bethe-Salpeter equation; contributed to nuclear astrophysics, stellar evolution, statistical mechanics, and plasma physics
Allan R. Sandage	1926-2010 American	identified the first quasar, and discovered many more; determined ages of many globular clusters
Vera Rubin	1928- American	measured rotation curves for distant galaxies and ultimately concluded that 90% or more of the universe is made of invisible dark matter
Irwin I. Shapiro	1929- American	implemented novel radio or radar techniques for various astrophysical research activities including solar-system tests of general relativity and studies of gravitational lenses and supernovae seeking to determine an accurate value for the Hubble constant
Riccardo Giacconi	1931- Italian	pioneer of x-ray astronomy; participated in discovery of the first known x-ray source outside the solar system (Scorpius X-1)
Sir Roger Penrose	1931- British	contributed to the development of general relativity by showing the necessity for cosmological singularities; elucidated the physics of black holes
John N. Bahcall	1934-2005 American	made important theoretical contributions to understanding solar neutrinos and quasars
Carl Sagan	1934-1996 American	was a leader in the search for extraterrestrial intelligence; contributed to most of the space missions to explore Mars and the outer planets; warned that all-out nuclear war could lead to a “nuclear winter”
James W. Christy	1938- American	discovered Pluto's satellite, Charon
William K. Hartmann	1939- American	well-known painter of astronomical themes; co-developed the most widely accepted theory of the formation of the Moon (from the collision of a giant planetismal with the Earth at the close of the planet-forming period of the solar system)
Kip S. Thorne	1940- American	contributed to the theoretical understanding of black holes and gravitational radiation; co-founded the Laser Interferometer Gravitational Wave Observatory Project (LIGO)
Bernard F. Burke	1942- American	developed techniques for very-long-baseline interferometry (VLBI) using atomic frequency standards to synchronize radio telescopes at remote locations worldwide, leading to a 1000-fold improvement in angular resolution for radio telescopes; conducted first measurements of intercontinental and transcontinental VLBI
Stephen W. Hawking	1942-2018 British	combined general relativity with quantum theory to predict that black holes should emit radiation and evaporate
Jocelyn Bell	1943- British	co-discovered the first pulsar
Charles Thomas Bolton	1943- American-born Canadian	identified Cygnus X-1 as the first black hole
James Ludlow Elliot	1943-2011 American	discovered the rings of Uranus
Alan H. Guth	1947- American	developed the theory of cosmic evolution known as the inflationary universe
Paul F. Goldsmith	1948- American	director of National Astronomy and Ionosphere Center; developed techniques to study structure of dense molecular clouds where star formation is occurring
Tadashi Nakajima	Japanese	led the group that discovered the first Brown Dwarf
Neil deGrasse Tyson	1958- American	best known for poplarizing science by hosting the television series NOVA ScienceNow and Cosmos: A SpaceTime Odyssey
Mike Brown	1965- American	discovered with his team many trans-Neptunian objects (TNOs) including Eris, the first TNO discovered that is larger than Pluto, which eventually led to the demotion of Pluto to a dwarf planet