Galaxy: Quick Facts

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Last updated

Nov. 13, 2026

News •

Scientists May Have Discovered a Massive Starless Galaxy • Nov. 9, 2026, 6:15 AM ET (WIRED)

A galaxy nicknamed Misty Moons offers a glimpse of early star formation • Nov. 6, 2026, 7:40 AM ET (Phys.org)

Three giant black holes discovered in a galaxy from the dawn of time • Oct. 25, 2026, 3:00 AM ET (Science Daily)

Astronomers Detect the Oldest Known Fast Radio Burst, Spewed From an Ancient Galaxy Just Three Billion Years After the Big Bang • Oct. 23, 2026, 1:17 PM ET (Smithsonian Magazine)

A Strange Radio Signal in The Far Reaches of The Milky Way Is Behaving Like Nothing Else in The Galaxy • Oct. 22, 2026, 4:07 PM ET (ScienceAlert)

Photos and Videos

Whirlpool Galaxy (M51); NGC 5195

Large Magellanic Cloud

Small Magellanic Cloud

globular cluster M80

centre of the Milky Way Galaxy

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 Hubble's system of galaxy classification, showing elliptical galaxies ranging from E0 to E7, and branching into S0, then into normal spiral galaxies (Sa, Sb, Sc) and barred spiral galaxies (SBa, SBb, SBc).

What are the three types of galaxies?

How the Hubble Space Telescope works—and why it's important

Understand gravitational lenses and the importance of tracking the dark matter

Learn about galaxy clusters, superclusters, and the Local Group

Understand the theoretical model of dark energy and the acceleration of the universe

See All Videos and Images →

Topics

irregular galaxy Star stellar population nucleus X-ray galaxy de Vaucouleurs classification radio galaxy external galaxy ultraluminous infrared galaxy spiral galaxy Cosmic microwave background Planet X-ray source Constellation Black hole Radio source Intergalactic medium Stellar association Infrared source Cosmic X-ray background

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Key People

Neil deGrasse Tyson

Neil deGrasse Tyson

American astronomer

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Harlow Shapley

American astronomer

Telescope at Birr Castle

William Parsons, 3rd earl of Rosse

Irish astronomer

Sir Martin Ryle.

Sir Martin Ryle

British astronomer

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Bertil Lindblad

Swedish astronomer

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

View of the Andromeda Galaxy (Messier 31, M31).

Astronomy and Space Quiz

27 True-or-False Questions from Britannica’s Most Difficult Science Quizzes

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

View of the Andromeda Galaxy (Messier 31, M31).

The Night Sky: Galaxies and Constellations