Cosmology: Quick Facts

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Last updated

Nov. 12, 2026

News •

How did the universe take shape? A new simulation offer clues • Nov. 11, 2026, 8:30 AM ET (CNN)

The latest in space science: We look back at the Big Bang • Oct. 23, 2026, 7:10 PM ET (NPR)

Forgotten particle could answer mystery of why we exist, say physicists • Oct. 19, 2026, 7:10 PM ET (Phys.org)

Photos and Videos

The Andromeda Galaxy, a bright spiral galaxy with a glowing core and swirling arms, appears against a dense field of stars in deep space.

Diagram illustrating the evolutionary theory of the universe, with two panels: one labeled Now showing clustered galaxies, and a second labeled Billions of years later showing the galaxies spread farther apart, indicating expansion over time. Red lines connect the galaxies to emphasize their increasing distances.

A grid representing spacetime is distorted by three spheres of different sizes, illustrating how massive objects curve spacetime according to general relativity.

experimental evidence for general relativity

Two diagrams illustrate intrinsic curvature: on the left, a dome-like bowl shape representing positive curvature; on the right, a saddle shape representing negative curvature.

Line graph comparing models of the universe's relative size over time, with time in billions of years on the x-axis and relative size on the y-axis. Multiple colored lines show different expansion scenarios, including ongoing expansion and a closed universe that contracts after reaching a maximum size. Present time and present size are marked with dashed lines.

Oval map of the cosmic microwave background radiation from NASA's WMAP mission, showing a mottled pattern of blue, green, yellow, and red representing temperature variations.

A sequence of five panels illustrates the early stages of the universe after the big bang. The first panel shows a bright explosion. The next panels depict the dense particle soup of quarks, leptons, and their antiparticles, then the formation of protons and neutrons, followed by the creation of atomic nuclei and finally atoms of hydrogen and helium, with radiation present throughout.

supernova 1987A in the Large Magellanic Cloud

gravitational lens

Examine the observable universe's place within the whole universe

Planck length: why string theory is hard to test

Explore Karl Schwarzschild's point of no return and the event horizons

Know about the Millennium Simulation at the Max Planck Institute for Astrophysics and learn how to simulate the universe on a personal computer

Listen to astrophysicist Neil deGrasse Tyson narrate a brief history of the formation of the universe, from the big bang to the present

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Topics

Cosmogony massive-neutrino hypothesis inhomogeneous nucleosynthesis hypothesis matter-antimatter asymmetry cosmography Multiverse Anthropic principle Universe Astronomy physics mechanics optics quantum mechanics thermodynamics Celestial mechanics electronics acoustics biophysics atomic physics Radio and radar astronomyradar astronomy

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Key People

Emanuel Swedenborg

Emanuel Swedenborg

Swedish philosopher

Giordano Bruno

Giordano Bruno

Italian philosopher

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George Gamow

American physicist

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Pascual Jordan

German physicist

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James Peebles

American physicist

Michał Heller

Michał Heller

Polish priest and mathematical cosmologist

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Sir Hermann Bondi

British scientist

Otto Heckmann at the European Southern Observatory's (ESO's) one-metre Schmidt telescope at La Silla, Chile, 1971.

Otto Heckmann

German astronomer

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Edward Arthur Milne

British astrophysicist

Georges Lemaître

Georges Lemaître

Belgian astronomer

Self-portrait of Leonardo da Vinci drawn in red chalk, showing an elderly man with long hair and a flowing beard, with a serious, contemplative expression.

Leonardo da Vinci

Italian artist, engineer, and scientist

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Rainer Weiss

American physicist

Etching by Jacob de Gheyn III showing Thales of Miletus seated with a long beard, draped in robes, holding a compass over an open book with geometric diagrams.

Thales of Miletus

Greek philosopher

Martin Rees

Martin Rees

British cosmologist and astrophysicist

Anaximander

Anaximander

Greek philosopher

Anaxagoras

Anaxagoras

Greek philosopher

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Robert H. Dicke

American physicist

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Anaximenes Of Miletus

Greek philosopher

Heraclitus

Heraclitus

Greek philosopher

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Empedocles

Greek philosopher and scholar

Horologist Roman Piekarski starts the time consuming task of adjusting the 600 antique clocks at Cuckooland Museum in readiness for this weekends change to British summer time on March 23, 2009 in Knutsford, England.

Ologies Quiz

Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.

All About Astronomy

Ursa major constellation illustration art. (Big Dipper) stars, space, night sky)

Stars: Explosions in Space

The orbits of the planets and other elements of the solar system, including asteroids, Kuiper belt, Oort cloud, comet

Space Odyssey