People Known for: sciences - astronomy

Johannes Kepler

German astronomer

Johannes Kepler, German astronomer who discovered three major laws of planetary motion, conventionally designated as follows: (1) the planets move in elliptical orbits with the Sun at one focus; (2) the…...

Galileo

Italian philosopher, astronomer and mathematician

Galileo, Italian natural philosopher, astronomer, and mathematician who made fundamental contributions to the sciences of motion, astronomy, and strength of materials and to the development of the scientific…...

Nicolaus Copernicus

Polish astronomer

Nicolaus Copernicus, Polish astronomer who proposed that the planets have the Sun as the fixed point to which their motions are to be referred; that Earth is a planet which, besides orbiting the Sun annually,…...

Giordano Bruno

Italian philosopher

Giordano Bruno, Italian philosopher, astronomer, mathematician, and occultist whose theories anticipated modern science. The most notable of these were his theories of the infinite universe and the multiplicity…...

Sir William Herschel

British-German astronomer

Sir William Herschel, German-born British astronomer, the founder of sidereal astronomy for the systematic observation of the heavens. He discovered the planet Uranus, hypothesized that nebulae are composed…...

Al-Bīrūnī

Persian scholar and scientist

Al-Bīrūnī, Muslim astronomer, mathematician, ethnographist, anthropologist, historian, and geographer. Al-Bīrūnī lived during a period of unusual political turmoil in the eastern Islamic world. He served…...

Henri Poincaré

French mathematician

Henri Poincaré, French mathematician, one of the greatest mathematicians and mathematical physicists at the end of 19th century. He made a series of profound innovations in geometry, the theory of differential…...

Ptolemy

Egyptian astronomer, mathematician, and geographer

Ptolemy, an Egyptian astronomer, mathematician, and geographer of Greek descent who flourished in Alexandria during the 2nd century ce. In several fields his writings represent the culminating achievement…...

Carl Friedrich Gauss

German mathematician

Carl Friedrich Gauss, German mathematician, generally regarded as one of the greatest mathematicians of all time for his contributions to number theory, geometry, probability theory, geodesy, planetary…...

Roger Bacon

English philosopher and scientist

Roger Bacon, English Franciscan philosopher and educational reformer who was a major medieval proponent of experimental science. Bacon studied mathematics, astronomy, optics, alchemy, and languages. He…...

Henry Norris Russell

American astronomer

Henry Norris Russell, American astronomer—one of the most influential during the first half of the 20th century—who played a major role in the establishment of modern theoretical astrophysics by making…...

Edwin Hubble

American astronomer

Edwin Hubble, American astronomer who played a crucial role in establishing the field of extragalactic astronomy and is generally regarded as the leading observational cosmologist of the 20th century.…...

Tycho Brahe

Danish astronomer

Tycho Brahe, Danish astronomer whose work in developing astronomical instruments and in measuring and fixing the positions of stars paved the way for future discoveries. His observations—the most accurate…...

Edmond Halley

British scientist

Edmond Halley, English astronomer and mathematician who was the first to calculate the orbit of a comet later named after him. He is also noted for his role in the publication of Isaac Newton’s Philosophiae…...

Sima Qian

Chinese historian and scientist

Sima Qian, astronomer, calendar expert, and the first great Chinese historian. He is most noted for his authorship of the Shiji (“Historical Records”), which is considered to be the most important history…...

Christiaan Huygens

Dutch scientist and mathematician

Christiaan Huygens, Dutch mathematician, astronomer, and physicist, who founded the wave theory of light, discovered the true shape of the rings of Saturn, and made original contributions to the science…...

Sir William Rowan Hamilton

Irish mathematician and astronomer

Sir William Rowan Hamilton, Irish mathematician who contributed to the development of optics, dynamics, and algebra—in particular, discovering the algebra of quaternions. His work proved significant for…...

Arthur Eddington

British scientist

Arthur Eddington, English astronomer, physicist, and mathematician who did his greatest work in astrophysics, investigating the motion, internal structure, and evolution of stars. He also was the first…...

Sir John Herschel, 1st Baronet

English astronomer

Sir John Herschel, 1st Baronet, English astronomer and successor to his father, Sir William Herschel, in the field of stellar and nebular observation and discovery. An only child, John was educated briefly…...

Pierre-Simon, marquis de Laplace

French scientist and mathematician

Pierre-Simon, marquis de Laplace, French mathematician, astronomer, and physicist who was best known for his investigations into the stability of the solar system. Laplace successfully accounted for all…...

Friedrich Wilhelm Bessel

German astronomer

Friedrich Wilhelm Bessel, German astronomer whose measurements of positions for about 50,000 stars and rigorous methods of observation (and correction of observations) took astronomy to a new level of…...

Sir Bernard Lovell

English radio astronomer

Sir Bernard Lovell, English radio astronomer, founder and director (1951–81) of England’s Jodrell Bank Experimental Station (now Jodrell Bank Observatory). Lovell attended the University of Bristol, from…...

Eudoxus of Cnidus

Greek mathematician and astronomer

Eudoxus of Cnidus, Greek mathematician and astronomer who substantially advanced proportion theory, contributed to the identification of constellations and thus to the development of observational astronomy…...

William Hyde Wollaston

British scientist

William Hyde Wollaston, British scientist who enhanced the techniques of powder metallurgy to become the first to produce and market pure, malleable platinum. He also made fundamental discoveries in many…...

Nicholas Oresme

French bishop, scholar, and economist

Nicholas Oresme, French Roman Catholic bishop, scholastic philosopher, economist, and mathematician whose work provided some basis for the development of modern mathematics and science and of French prose,…...

Simon Newcomb

American astronomer and mathematician

Simon Newcomb, Canadian-born American astronomer and mathematician who prepared ephemerides—tables of computed places of celestial bodies over a period of time—and tables of astronomical constants. Newcomb…...

George Ellery Hale

American astronomer

George Ellery Hale, American astronomer known for his development of important astronomical instruments, including the Hale Telescope, a 200-inch (508-cm) reflector at the Palomar Observatory, near San…...

Omar Khayyam

Persian poet and astronomer

Omar Khayyam, Persian mathematician, astronomer, and poet, renowned in his own country and time for his scientific achievements but chiefly known to English-speaking readers through the translation of…...

Al-Kāshī

Persian astronomer and mathematician

Al-Kāshī, ranks among the greatest mathematicians and astronomers in the Islamic world. The first event known with certainty in al-Kāshī’s life is his observation of a lunar eclipse on June 2, 1406, from…...

Regiomontanus

German mathematician

Regiomontanus, the foremost mathematician and astronomer of 15th-century Europe, a sought-after astrologer, and one of the first printers. Königsberg means “King’s Mountain,” which is what the Latinized…...

Ibn al-Haytham

Arab astronomer and mathematician

Ibn al-Haytham, mathematician and astronomer who made significant contributions to the principles of optics and the use of scientific experiments. Conflicting stories are told about the life of Ibn al-Haytham,…...

James Bradley

English astronomer

James Bradley, English astronomer who in 1728 announced his discovery of the aberration of starlight, an apparent slight change in the positions of stars caused by the yearly motion of the Earth. That…...

Carl Sagan

American astronomer

Carl Sagan, American astronomer and science writer. A popular and influential figure in the United States, he was controversial in scientific, political, and religious circles for his views on extraterrestrial…...

Viktor Amazaspovich Ambartsumian

Armenian astronomer

Viktor Amazaspovich Ambartsumian, Soviet astronomer and astrophysicist best known for his theories concerning the origin and evolution of stars and stellar systems. He was also the founder of the school…...

Franz Xaver von Zach

German-Hungarian astronomer

Franz Xaver von Zach, German Hungarian astronomer noted for being the nexus of astronomical information in Europe in the early 19th century. Zach was educated at a Jesuit seminary and later evinced extreme…...

Thomas Harriot

English mathematician and astronomer

Thomas Harriot, mathematician, astronomer, and investigator of the natural world. Little is known of him before he received his bachelor’s degree from the University of Oxford in 1580. Throughout his working…...

Geoffrey Marcy

American astronomer

Geoffrey Marcy, American astronomer whose use of Doppler shifts to detect extrasolar planets led to the discovery of several hundred planetary bodies in multiple star systems. Marcy was raised in the suburbs…...

Moon, Earth, and Sun diagrammed in Aristarchus's On the Sizes and Distances of the Sun and Moon

Aristarchus of Samos

Greek astronomer

Aristarchus of Samos, Greek astronomer who maintained that Earth rotates on its axis and revolves around the Sun. On this ground, the Greek philosopher Cleanthes the Stoic declared in his Against Aristarchus…...

Robert Hooke

British scientist

Robert Hooke, English physicist who discovered the law of elasticity, known as Hooke’s law, and who did research in a remarkable variety of fields. In 1655 Hooke was employed by Robert Boyle to construct…...

James Gregory

Scottish mathematician and astronomer

James Gregory, Scottish mathematician and astronomer who discovered infinite series representations for a number of trigonometry functions, although he is mostly remembered for his description of the first…...

Neil deGrasse Tyson

American astronomer

Neil deGrasse Tyson, American astronomer who popularized science with his books and frequent appearances on radio and television. When Tyson was nine years old, his interest in astronomy was sparked by…...

Cecilia Payne-Gaposchkin

British-born American astronomer

Cecilia Payne-Gaposchkin, British-born American astronomer who discovered that stars are made mainly of hydrogen and helium and established that stars could be classified according to their temperatures.…...

Naṣīr al-Dīn al-Ṭūsī

Persian scholar

Naṣīr al-Dīn al-Ṭūsī, outstanding Persian philosopher, scientist, and mathematician. Educated first in Ṭūs, where his father was a jurist in the Twelfth Imam school, the main sect of Shīʾite Muslims, al-Ṭūsī…...

Harlow Shapley

American astronomer

Harlow Shapley, American astronomer who deduced that the Sun lies near the central plane of the Milky Way Galaxy and was not at the centre but some 30,000 light-years away. In 1911 Shapley, working with…...

Martin Rees

British cosmologist and astrophysicist

Martin Rees, English cosmologist and astrophysicist who was a main expositor of the big-bang theory of the origins of the universe. Rees was raised in Shropshire, in the English Midlands. After receiving…...

Annie Jump Cannon

American astronomer

Annie Jump Cannon, American astronomer who specialized in the classification of stellar spectra. Cannon was the eldest daughter of Wilson Cannon, a Delaware state senator, and Mary Jump. She studied physics…...

Anaximander

Greek philosopher

Anaximander, Greek philosopher who was the first to develop a cosmology, or systematic philosophical view of the world. Only a short fragment of Anaximander’s work survives, so reconstructions of his philosophy…...

Henrietta Swan Leavitt

American astronomer

Henrietta Swan Leavitt, American astronomer known for her discovery of the relationship between period and luminosity in Cepheid variables, pulsating stars that vary regularly in brightness in periods…...

Gian Domenico Cassini

French astronomer

Gian Domenico Cassini, Italian-born French astronomer who, among others, discovered the Cassini Division, the dark gap between the rings A and B of Saturn; he also discovered four of Saturn’s moons. In…...

Aryabhata

Indian astronomer and mathematician

Aryabhata, astronomer and the earliest Indian mathematician whose work and history are available to modern scholars. He is also known as Aryabhata I or Aryabhata the Elder to distinguish him from a 10th-century…...

PEOPLE KNOWN FOR: astronomy