Astronomy Timeline

Hipparchus

Jan 1, 1000

-born in 190 BC
-is known for finding numerical data from observations into geometric models
-discovered the precession of the equinoxes http://space.about.com/od/astronomerbiographies/a/hipparchusbio.htm

Ancient Greek Astronmy

Jan 1, 1000

-looked at astronomy in the sense of math instead of making observations
-this is how they discovered that the Earth orbits around the sun
-also calculated the size of the Earth http://www.historyforkids.org/learn/greeks/science/astronomy/

Aristarchus of Samos

Jan 1, 1000

-born in 310 BC
-first to suggest that the Earth revolves on an axis and moves around the sun
-his ideas were not accepted until the 1500s
-He used Euclid's geometric theories, and his own, to do his calculations http://www.historyforkids.org/learn/greeks/science/math/aristarchus.htm

Aristotle

Jan 1, 1000

-born 384 B.C
-Influenced Western thought
-discussed the systematic understanding of logic, physics, and astronomy,
-know for his diverse explainations of phyics, government, ethics, zoology http://www.wsu.edu/~dee/GREECE/ARIST.HTM

Eratosthenes

Jan 1, 1000

-born in 276 BC
-first person to find the actual circumference of the Earth
-he measured shadows in two different towns at the same time of day, then mesaured the distances between the two towns and calculated the circumference of the Earth http://www.windows2universe.org/people/ancient_epoch/eratosthenes.html

Pythagoras

Jan 1, 1000

-born 569 B.C.
-invented the Pythagorean Theorem in geometry
-"first pure mathematician"
-little is known about his life, due to he lived in a secrecy enviroment http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Pythagoras.html

Copernicus

Feb 19, 1473

-he believed the sun was the stationary center of the solar system and the Earth revolved around it
-first to propose the idea of a heliocentric cosmology http://library.thinkquest.org/23830/copernicus.htm

Tycho Brahe

Dec 14, 1546

-discovered the first "new star" which was supernova
-thought the Earth was the centre of the universe, and the other planets were satellites of the sun http://www.biographybase.com/biography/Brahe_Tycho.html

Galileo Galilei

Feb 15, 1564

-Kinematics, dynamics, telescopic observational astronomy and heliocentrism
-discovered four satellites in orbit around Jupiter
-one of the first people to observe sunspots http://www.brighthub.com/science/space/articles/36995.aspx

Johannes kepler

Dec 27, 1571

-know for his formulations of verifying the three laws of planetary motion. (later became know as Kepler's Laws)
-Wrote a book on how all the planets orbital periods are at a constant and are all the same
-proposed that the sun produced a force that diminishes the distance and pushes the planets around their orbits http://library.thinkquest.org/23830/kepler.htm

Isaac Newton

Dec 25, 1642

-discovered the 3 laws of motion
-usually refered to as the "most original and influential theorist in the history of science"
-Realized the moons circular path around the Earth was caused by gravitational pull http://www.clas.ufl.edu/users/ufhatch/pages/01-courses/current-courses/08sr-newton.htm

Annie Jump Cannon

Dec 11, 1863

-studied variable stars and stellar spectra
-she published a catalog of 1,122 southern stars, which represented a continuous change from the blue-white stars, later this was founded as temperature sequence
-published the "Henry Draper Catalogue", which listed spectral types, magnitudes, and positions of 225,300 stars http://www.answers.com/topic/annie-jump-cannon

George Hale

Jun 29, 1868

-invented the spectroheliograph, which he used to study features of the sun
-founded 3 observatories
-made observations that the sun spots were cooler than the surrounding area and they were strongly magnectic http://www.answers.com/topic/george-ellery-hale

Henrietta Swan Leavitt

Jul 4, 1868

-discovered Luminosity
-used plates to discover a stars magnitude and used "the north polar sequence" to detemine the stars brightness
-determined the distances between stars by light years http://www.womanastronomer.com/hleavitt.htm

Albert Einstein

Mar 14, 1879

-formulated the Special Theory of Relativity
-formulated the Mass-Energy relations
-1921 Nobel prize in physics http://www.teslasociety.com/einstein.htm

Edwin Hubble

Nov 29, 1889

-California's Mount Wilson Observatory
-Discovered Cepheids were outside of the Milky Way Galaxy, proving the existance of other galaxies
-1929 invented Hubble's Law, which let other astronomiers determine the actual age of universe http://www.best-telescope-guide.com/facts-about-edwin-hubble.html

Gerard Kuiper

Dec 7, 1905

-Kuiper Belt was proposed by him in 1951
-Kuiper belt consist of disk shaped minor planets outisde of the orbit of Neptune. short-period comets come out of this area
-also he discovered Saturn's satellite moon and the carbon dioxide atmosphere of Mars http://www.nnp.org/nni/Publications/Dutch-American/kuiper.html

Bengt Georg Daniel Stromgren

Jan 21, 1908

-found relations between the gas density, the luminosity of the star, and the size of the “Strömgren sphere” of ionized hydrogen around it
-1930: research in stellar structure
-is best known for his work on ionized gas clouds http://phys-astro.sonoma.edu/BruceMedalists/Stromgren/

Subrahmanyan Chandrasekhar

Oct 19, 1910

-the first person to theorize that a collapsing massive star would become an object so dense that not even light could escape it
-formed the foundation of the theory of black hole
-theorems on the stability of cosmic masses in the presence of gravitation, rotation, and magnetic fields http://www.nationalacademies.org/history/members/chandrasekhar.html

Grote Reber

Dec 22, 1911

-built the first radio telescope
-discovered radio waves from Cygnus and Cassiopeia for the first time
-discovered radio waves at very low frequencies http://www.nrao.edu/whatisra/hist_reber.shtml

James Van Allen

Sep 7, 1914

-discovered that radiation belts surround the Earth, now radiations fields around the earth are commonly refered to as "Van Allen belts"
-explored the outer reaches of earth's atmosphere and the magnetosphere http://history.nasa.gov/sputnik/vanallen.html

Sir Fred Hoyle

Jun 24, 1915

-Made predictions 10 years before the dawn of space flight, that all came true
-Developed the steady-state cosological theory and rephased the 'Big Band' theory on BBC radio in 1949
-His wife and him published books about their predictions http://pagerankstudio.com/Blog/2010/09/sir-fred-hoyle-biography-life-and-career-facts-invented/

E. Margaret Burbidge

Aug 12, 1919

-helped/planned and outfitted the Hubble Space Telescope
-recognized for the production of the first accurate estimate of the masses of galaxies
-known for her work with quasars, and for work she did concerning the metal contents of stars http://www.answers.com/topic/margaret-burbidge

Eugene Shoemaker

Apr 28, 1928

-pioneer work in elucidating the mechanics of impacts and discovering of Earth-crossing bodies
-1933 he discovered a comet that would strike Jupiter 16 months later
-led the leading comet discoverers of this century
-discovered more than 800 asteroids http://users.zoominternet.net/~matto/M.C.A.S/eugene_shoemaker.htm

Thomas Mutch

Aug 26, 1931

-published two books about the Moon and Mars
-presumed killed when he disappeared in Mount Nun
-He has a crater on Mars named after him
- Led the Lander Imaging team from the Viking Mission to Mars http://www.brown.edu/Departments/Geology/colloquia/mutch.html