The 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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Revealing the Start of Time Itself: Ripples in the Fabric of the Universe May Peer Back to the Beginning of Everything We Know

Ancient humans and their early depictions of the universe: “It is no exaggeration to say that astronomy has existed as an exact science for more than five millennia,” writes the late science historian John North.

Using the Shadows of Clusters to Measure the Universe

Let’s Hack the Universe

These ‘green pea’ galaxies might have helped to end the Universe’s dark age

Challenging Our Understanding of the Universe: Astronomers Discover an Enigmatic Cosmic Explosion

Unlocking the Secrets of the Universe: Researchers Use High-Powered Lasers to Study Magnetic Reconnection

This Week @NASA: Space Exploration Collaboration, Webb Reveals Galaxies From Dawn of the Universe

The Secret Code of the Universe: A Remarkable Way of Measuring the Fine Structure Constant

Astronomers May Have Just Spotted the Universe’s First Galaxies

Why maths, our best tool to describe the universe, may be fallible

Searching for the earliest galaxies in the universe

How Star Collisions Forge the Universe's Heaviest Elements

Our Mental Picture of Space Seems to Expand Like The Universe

Scientists will present new research from NASA at the 241st meeting of the American Astronomical Society (AAS), on topics ranging from the universe’s early galaxies to planets outside our solar system

All the Gold in the Universe Was (Likely) Created This Way

The brain's ability to perceive space expands like the universe

We're on The Brink of Hearing The Universe's Background Hum. Here's Why We're Listening

Study Shows How The Universe Would Look if You Broke The Speed of Light, And It's Weird

'The Short Story of the Universe' fits a big topic into your pocket