Starts With A Bang

The universe is out there, waiting to be discovered

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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.

with Ethan Siegel

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

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A bald man with a long beard and handlebar mustache gestures with his hands against a backdrop of an upside-down cityscape wearing a purple shirt.

Groupthink in science isn’t a problem; it’s a myth

Scientists are notoriously resistant to new ideas. Are they falling prey to groupthink? Or are our current theories just that successful?

by Ethan Siegel

Everything Articles

Visualization of a section through the large-scale structure of the universe highlighting cosmic web patterns and distributions.

Starts With A Bang

Ask Ethan: Is dark energy just leftover momentum from the Big Bang?

Since 1998, we've known our Universe isn't just expanding, but the expansion is accelerating. Could the Big Bang itself be the reason why?

Ethan Siegel

Starts With A Bang

The 6 strongest materials on Earth are harder than diamonds

For millennia, diamonds were the hardest known material, but they only rank at #7 on the current list. Can you guess which material is #1?

Ethan Siegel

A man in a suit holds up a Hurricane Dorian forecast map in an office, tracing the storm’s projected path and intensity over several southeastern U.S. states and the Bahamas—echoing the urgent clarity of a 1938 science manifesto defending democracy.

Starts With A Bang

This 1938 pro-science manifesto defended democracy against fascism

As democracy recedes and fascism rises in the USA and around the world in 2025, history provides a lesson in how science can fight fascism.

Ethan Siegel

Illustration of a large particle accelerator facility underground, with scientists working and a city landscape above ground.

Starts With A Bang

A new collider can teach us about the origin of matter

The laws of nature are almost perfectly symmetric between matter and antimatter, and yet our Universe is made ~100% of matter only. But why?

Ethan Siegel

A repeating pattern of wireframe 3D geometric shapes intersected by diagonal yellow lines on a black background, evoking a physics break down of forms at the Planck scale.

Starts With A Bang

Why does physics break down at the Planck scale?

There are limits to where physics makes meaningful predictions: beyond the Planck length, time, or energy. Here's why we can't go further.

Ethan Siegel

$Bright star at the center of a blue nebula radiates mass energy, surrounded by numerous smaller stars, with diffraction spikes visible from the brightest stars.$

Starts With A Bang

Ask Ethan: When do stars turn the most mass into energy?

All stars shine due to an internal source of energy. Usually, it's nuclear fusion: converting mass into energy. What makes them most bright?

Ethan Siegel