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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: How are black holes active if nothing escapes from them?
Once you cross over to the inside of an event horizon, you can never come out again. But then, how do black holes emit all sorts of things?
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?
In 2006, Pluto was controversially demoted to "dwarf planet" by the IAU. Unless you ignore most of astrophysics, it won't ever be one again.
The first colliding galaxy cluster to reveal dark matter, empirically, turns 20 this year. Here's why it cements dark matter's existence.
NASA has just sent astronauts back to the Moon for the first time since 1972 with Artemis II. So why would we cut NASA and NSF science now?
Today, we have the Standard Model of particles with four fundamental forces governing them. But things weren't always the way they are now.
Many facts are well-known to professionals, but are unappreciated or even rejected outright by the public. "How stars work" takes the cake.
For decades, theorists have been cooking up "theories of everything" to explain our Universe. Are all of them completely off-track?
Our dream of journeying to other star systems has a big obstacle to overcome: the vast interstellar distances. Can antimatter get us there?
On cosmic scales, only dark matter (or something equivalent) gives us the Universe we observe. Now, the Sunyaev-Zel'dovich effect agrees.
Although a star's "birth" is well-defined, it doesn't correspond to an ignition event in its core. Here's how stars are actually born.