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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.
Move over, giant meteor. Here’s what the largest comet would do to Earth
Oort cloud object Bernardinelli–Bernstein has the largest known cometary nucleus: 119 km wide. An impact with Earth would be catastrophic.
The Universe took a great many steps to create not just life, but intelligent life, here at home. What can we say about life beyond Earth?
The anthropic principle has fascinating scientific uses, where the simple fact of our existence holds deep physical lessons. Don't abuse it!
Vast arrays of planets, stars, black holes, galaxies, and more populate our Universe. Within each category, differences can be astounding.
Contracting gas clouds don't just make a single star, but a spectrum, with all different masses. Early on, that spectrum differed. But why?
Protons and neutrons are composite structures: made of quarks and gluons. But knowing they had substructure goes back long before that.
Yes, "the laws of physics break down" at singularities. But relativity itself would have to be wrong for black holes to not possess them.
It's the Universe's ultimate chicken-and-egg question: what came first, the galaxy or the black hole? One Little Red Dot proves the answer.
In 2016, humanity announced our first successful gravitational wave detection. 10 years and 389 events later, here's how far we've come.
The Astro2020 decadal report set the USA's agenda for space and ground-based astronomy. Here in 2026, we're clearly on the wrong course.
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.