Best Astronomer

During her doctoral research in 1967, Jocelyn Bell Burnell identified unusual, regularly repeating signals in radio telescope records. These observations led to the discovery of pulsars, rapidly rotating neutron stars whose radiation can be detected as repeated pulses. Her careful attention to an un...

Subrahmanyan Chandrasekhar was a twentieth-century astrophysicist whose mathematical work transformed understanding of stellar structure and evolution. His best-known result, the Chandrasekhar limit, describes the maximum mass of a white dwarf supported by electron degeneracy pressure, the quantum e...

Cecilia Payne, later Cecilia Payne-Gaposchkin, was a British-born astronomer whose 1925 doctoral thesis changed the understanding of stellar composition. Using spectroscopy, the analysis of light separated into its component wavelengths, she concluded that stars contain far more hydrogen and helium...

Polish astrophysicist Bohdan Paczynski made influential contributions to the study of stars and energetic events during the twentieth century. Gravitational microlensing became a major part of his scientific legacy. This effect occurs when the gravity of a foreground object temporarily magnifies the...

American astronomer Andrea M. Ghez studies the center of the Milky Way, where observations of stellar motion reveal an extreme gravitational environment. Her team's work tracking stars near Sagittarius A* provided evidence for a supermassive black hole at the galactic center. The case depends on how...

Working in Alexandria during the second century CE, Claudius Ptolemy was a Greek-speaking astronomer whose Almagest organized a detailed mathematical account of the heavens. Written around 150 CE, it placed a stationary Earth at the center and used geometric models to calculate the apparent motions...

Yakov Borisovich Zel'dovich (1914-1987) was a Soviet physicist whose work extended from physical chemistry and nuclear physics to astrophysics and cosmology. He played a leading role in the Soviet nuclear weapons program, while his later scientific work addressed questions about the universe on scal...

John Archibald Wheeler (1911-2008) was an American theoretical physicist whose research ranged from nuclear physics to general relativity and quantum mechanics. He helped popularize the term black hole in 1967, giving a memorable name to a concept he did not originate. His work with Niels Bohr contr...

Born in 1941, Joseph Hooton Taylor Jr. is an American astrophysicist associated with precision studies of pulsars. He shared the 1993 Nobel Prize in Physics with Russell Hulse for the discovery of the first binary pulsar, identified in 1974 using the Arecibo Observatory. The system, PSR B1913+16, of...

Edmond Halley (1656–1742) was an English astronomer, mathematician, and geophysicist who served as the second Astronomer Royal from 1720 until his death. In 1705 he published A Synopsis of the Astronomy of Comets, in which he calculated the orbits of two dozen comets and predicted that sightings in...

Bohdan Paczyński was a prominent Polish astrophysicist who made major contributions to the study of stellar evolution, particularly regarding mass transfer in binary star systems. He was also a pioneer in the field of gravitational microlensing, developing observational techniques to detect dark mat...

Jan Hendrik Oort was a Dutch astronomer whose research fundamentally shaped modern understanding of the Milky Way galaxy. In 1927, he provided evidence that the galaxy is rotating by analyzing the motions of stars, and he later calculated the distance from the sun to the galactic center. Oort also p...

John N. Bahcall was a prominent American astronomer specializing in solar physics and neutrino research. His meticulous work analyzing solar neutrino data challenged prevailing theoretical models regarding the Sun's energy production. He played a key role in understanding these fundamental particles...

Charles L. Bennett is an American observational cosmologist who served as principal investigator for NASA's Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001. WMAP produced the most precise full-sky map of the cosmic microwave background then available, yielding refined measurements of t...

Dame Margaret Burbidge fundamentally advanced our understanding of stellar evolution and galactic chemical enrichment. Her groundbreaking 1957 research, co-authored with Joseph Lickter and Geoffrey Taylor, proposed the “nucleosynthesis” theory – detailing how stars create elements heavier than hydro...

Eleanor Margaret Burbidge was a pioneering British astronomer renowned for her significant contributions to our understanding of galactic evolution. She developed groundbreaking techniques in spectroscopy to study distant stars and galaxies. Her work, particularly co-authoring the pivotal 1957 B2FH...

Jan Oort was a twentieth-century Dutch astronomer whose work fundamentally shaped our understanding of the Milky Way galaxy. He determined the galaxy’s rotation curve in the 1920s and subsequently theorized the existence of the Oort cloud – a vast, distant reservoir of icy bodies believed to surroun...

William Herschel was an eighteenth-century astronomer renowned for his pioneering work with telescopes. He significantly advanced astronomical observation by constructing powerful reflecting instruments. His most celebrated achievement was the discovery of Uranus in 1781, a finding that dramatically...

Hannes Alfvén was a Swedish plasma physicist and electrical engineer who made foundational contributions to the field of plasma physics. He is best known for developing magnetohydrodynamics, a framework that describes the behavior of electrically conducting fluids like plasma in magnetic fields. Thi...

Bohdan Paczyński was a prominent Polish astronomer known for his groundbreaking work on gamma-ray bursts and gravitational microlensing. His innovative techniques, particularly utilizing telescopes to detect faint light distortions caused by distant stars, significantly advanced the study of stellar...

Uroš Seljak is a Slovenian-American cosmologist who has made significant contributions to the understanding of cosmic microwave background radiation and the large-scale structure of the universe. He co-developed the widely-used HaloFit model for predicting the nonlinear matter power spectrum and has...

Alexandre Friedmann was a Russian and Soviet physicist and mathematician who made significant contributions to cosmology. In 1922 and 1924, he published papers outlining the Friedmann equations, which provided exact solutions to Albert Einstein's field equations of general relativity. His work demon...

Edward Mills Purcell was an American physicist who spent his career at Harvard University. He is recognized for his independent discovery of nuclear magnetic resonance in liquids and solids, a breakthrough that earned him a shared Nobel Prize in Physics in 1952. In 1951, Purcell and his student Haro...

Robert H. Dicke was a prominent American astronomer who led research at Princeton University focused on cosmology. His team’s development of highly sensitive radiometers provided crucial data for interpreting the cosmic microwave background radiation discovered in 1965. This work significantly advan...

Lyman Spitzer Jr. was an American astronomer renowned for his pioneering research into interstellar space and plasma physics during the 20th century. His 1946 proposal for a space telescope anticipated modern observatories’ crucial role in studying distant stars and galaxies. Spitzer's work remains...

Matias Zaldarriaga is a prominent Argentine-American theoretical astrophysicist specializing in cosmology. He is a professor at the Institute for Advanced Study in Princeton, New Jersey. Zaldarriaga is widely recognized for his influential research on the cosmic microwave background (CMB) and the la...

Joseph von Fraunhofer was a 19th-century German physicist and optician who made significant advancements in the manufacturing of high-quality optical glass. While examining the spectrum of sunlight in 1814, he discovered and cataloged hundreds of dark absorption lines, which are now known as Fraunho...

J. Richard Bond is a Canadian theoretical cosmologist and professor at the University of Toronto. He has contributed to the understanding of the cosmic microwave background (CMB) radiation, structure formation in the universe, and theoretical cosmology more broadly. He served as director of the Cana...

John Mather is a prominent modern astronomer specializing in cosmology. He received the 2006 Nobel Prize in Physics for his groundbreaking work analyzing data from the Cosmic Background Explorer (COBE) satellite. His research significantly advanced our understanding of the early universe and its for...