Starts With A Bang

A dense starfield, with various colored stars shimmering through a dark cloud-like formation, lies against a deep black background in the mysterious zone of avoidance.
The Universe is out there, waiting to be discovered

Our mission is to answer the biggest questions of all, scientifically.

What is the Universe made of? How did it become the way it is today? Where did everything come from? What is the ultimate fate of the cosmos?

For most of human history, these questions had no clear answers. Today, they do. Starts With a Bang, written by Dr. Ethan Siegel, explores what we know about the universe and how we came to know it, bringing the latest discoveries in cosmology and astrophysics directly to you.

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Ethan Siegel is an award-winning PhD astrophysicist and the author of four books, including The Grand Cosmic Story, published by National Geographic.

Full Profile
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Ethan Siegel

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Visualization of the timeline of the universe, from the beginning big bang to the present.
The Universe is expanding, the expansion is accelerating, and some galaxies even recede faster-than-light. Can we see a change in real time?
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Even the most brilliant mind in history couldn't have achieved all he did without significant help from the minds of others.
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Side-by-side comparison of the Pillars of Creation in space, showing Hubble's visible light image and JWST's infrared image. Labels indicate "Hubble (Visible)" and "JWST (Infrared)".
Here in our modern Universe, it's cosmic dust that forms planets, complex molecules, and enables life. But how did the Universe create it?
star vs planet vs brown dwarf
13.8 billion years have passed since the Big Bang, but many stars will survive for longer than that. What's the longest-lived a star can be?
Two bright celestial objects, including the brightest planet, shine in the night sky, partially obscured by clouds and surrounded by smaller, faint stars.
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A dense field of distant galaxies and bright stars against a black background, as captured in a JWST early galaxies deep space telescope image.
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connected entangled pair
A century ago, quantum physics overthrew our view of a deterministic Universe. A profound 21st century theorem closes the door even further.
Image of a star field with numerous galaxies; several objects are circled in white, and one object is marked with an “X” near the center.
The Universe formed stars, galaxies, and even galaxy clusters extremely early on in our cosmos. This new marvel is one more JWST surprise.
cosmic rays
At the upper limits of what's energetically possible, cosmic rays still persist. What happens if a human gets hit by the most energetic one?
Our great hope is that today's indirect, astrophysical evidence will someday lead to successful direct detection. What if that's impossible?
A deep space image showing a field of distant galaxies with several regions zoomed in to highlight faint, small JWST objects.
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moon landing Apollo 11
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venus jupiter earth iss
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Raisin bread expanding Universe
Even in an expanding Universe, we expect both redshifted and blueshifted galaxies. But nearly every one we see is redshifted. Here's why.
An elderly woman wearing glasses, a black hat, and a patterned scarf smiles while seated indoors—reminiscent of Gladys West, the Einstein behind GPS technology.
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