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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.
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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.
Ask Ethan: Why does our Universe require CP-violation?
Two discrete symmetries, charge conjugation and parity, must be violated together for our Universe to exist. We haven't found enough of it.
Many people, now with LLM assistance, regularly claim to discover game-changing revolutions. Scientists don't buy it. You shouldn't either.
Despite all that we've discovered, Earth remains the only planet definitively known to possess life. Here's how to find a second example.
CERN's Large Hadron Collider superseded Fermilab's TeVatron in 2008, but now nears the end of its run. The ambitious FCC project comes next.
At and beyond the current frontiers of knowledge, many physicists have strongly held opinions. Can surveys point the way to breakthroughs?
The original idea of the Big Bang was synonymous with a singularity: a point of zero volume. In this Universe, things never got that small.
Theoretical physics is notorious for wild ideas that seem, at first, to be nonsensical fantasies. That's where the tooth fairy comes in.
Astronomers study our cosmic history through stellar and galactic archaeology. But we can't conduct archaeology in space. At least, not yet.
Light pollution now steals a pristine night sky from the majority of humanity. The rise of LED lighting, primarily since 2014, is to blame.
Today, in the here-and-now, a full 13.8 billion years have elapsed since the start of the hot Big Bang. But would that be true for everyone?
In physics, we reduce things to their elementary, fundamental components, and build emergent things out of them. That's not the full story.
Messier 77 is one of the largest nearby spiral galaxies, with an active, brilliant core. Here's what JWST's incomparable eyes saw inside it.
A relatively tiny world in the Kuiper belt, just 500 km in diameter, has an atmosphere after all, joining Pluto. Here's what we know today.
Only nearby objects appear to the naked eye. With telescopes of all types, especially in space, we've smashed those records many times over.
Triton is Neptune's largest moon today, but it was once the undisputed king of the Kuiper belt. Here's why the outer solar system matters.
There's a lot of room in interplanetary, interstellar, and intergalactic space, but just how low the densities go is truly mind-boggling.
Contrary to common experience, not everything needs a medium to travel through. Overcoming that assumption removes the need for an aether.
Newton's gravitational constant, G, is still known to just 3 significant figures in 2026. New measurements merely highlight our uncertainty.
In 2006, the IAU defined "planet" for the first time, excluding Pluto and all other dwarf planets. In 2026, is it now time for a change?
From within our own galaxy to behemoths billions of light-years away, supermassive black holes create jets like nothing else in the cosmos.
It takes incredible energies to accelerate masses near the speed of light. So how do the farthest galaxies speed away from us so quickly?