Universe

The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. According to this theory, space and time emerged together 13.787±0.020 billion years ago, and the universe has been expanding ever since the Big Bang. While the spatial size of the entire universe is unknown, it is possible to measure the size of the observable universe, which is approximately 93 billion light-years in diameter at the present day. Some of the earliest cosmological models of the universe were developed by ancient Greek and Indian philosophers and were geocentric, placing Earth at the center. Over the centuries, more precise astronomical observations led Nicolaus Copernicus to develop the heliocentric model with the Sun at the center of the Solar System.

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A Universe Without Dark Matter? Radical New Model Challenges Modern Cosmology

Scientists Trap a Single Antimatter Particle for Months in Quest To Solve the Universe’s Biggest Mystery

JWST Detects a 'Forbidden' Signal Never Before Seen in The Universe – Not Even in a Lab

Astronomers Discover Nāpōwawāʻenakaulua, the Oldest Compact Quasar Pair in the Universe

A massive new simulation reveals how the universe emerged from darkness

NASA's new UVEX space telescope will peer deep into the universe's most violent events

A radical theory says the universe is twice as old as we thought

Gravity May Protect The Universe From Time Travel Paradoxes, But There's a Catch

Astronomers discover Nāpōwawāʻenakaulua, the oldest compact quasar pair in the universe

First Direct Measurement of Cosmic Hydrogen Could Change How We Map the Universe

James Webb Discovers a Nearly Pristine Galaxy From the Dawn of the Universe

Scientists Reach a Record Temperature: 280 Billion Times Colder Than The Universe

An alternative model in which the Universe is 26.7 billion years old and needs neither dark matter nor dark energy has held up against several major cosmology tests, warranting further investigation

'Crisis averted' as experts confirm universe's expansion IS accelerating

Theory predicting an older Universe without dark matter or dark energy passes key cosmological tests, warranting further investigation

Pinning down the structure of quark-gluon plasma, the universe’s first fluid

New Jersey National Laboratory plumbs the universe

Astronomers find dust-shrouded star cluster near the center of the Milky Way that may be nearly as old as the universe, with an estimated age of 13.4 billion years: "If it was born here and is really this old, we may need to rethink the age of the galaxy, and possibly even of the universe"

A Strange New Theory Helps Explain Why Our Universe Has Only One Dimension of Time