dark energy: Quick Facts

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Oct. 26, 2026

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Photos and Videos

three Type Ia supernovas

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.

Two pie charts compare the universe's matter-energy content: 13.8 billion years ago, dark matter made up 63%, photons 15%, atoms 12%, and neutrinos 10%. Today, dark energy dominates at 69.4%, with dark matter at 26.1% and atoms at 4.5%.

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

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Topics

How will the Roman Space Telescope learn about dark energy and dark matter?outer space Universe dark matter Star Sun Eclipse Galaxy Cosmology gravity Solar system Star cluster Cosmic microwave background

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Astronomy: Dark energy

Key People

Adam Riess

Adam Riess

American astronomer

Brian P. Schmidt.

Brian P. Schmidt

American-born Australian astronomer

Saul Perlmutter

Saul Perlmutter

American physicist

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.

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