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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.
A brief history of the cosmic distance record
Only nearby objects appear to the naked eye. With telescopes of all types, especially in space, we've smashed those records many times over.
The combination of charge conjugation, parity, and time-reversal symmetry is known as CPT. And it must never be broken. Ever.
In theory, the fabric of space could have been curved in any way imaginable. So why is the Universe flat when we measure it?
Binary black holes eventually inspiral and merge. That's why the OJ 287 system is destined for the most energetic event in history.
Over billions of years, fewer stars form, galaxies mutually recede, and the Universe becomes ever darker. Here's how fast it all happens.
Nothing lives forever, at least, not in the known Universe. But relativity allows us to get closer than ever: from a physics perspective.
The path to exploring the high-energy Universe was clear and compelling. Here's how 2025's cuts are still causing NASA casualties in 2026.
Not everyone accepts the scientific consensus; some even make careers out of challenging it. But only a select few do it the right way.
Resembling a cosmic brain, the Exposed Cranium Nebula instead shows a dying, massive star, as JWST reveals. Its fate remains uncertain.
What goes up into low-Earth orbit will eventually come down, bringing huge consequences with it. Be informed, not surprised!
In traveling through the expanding Universe, particles slow down while light and gravitational waves redshift. What degrades and what won't?
Smashing things together at unprecedented energies sounds dangerous. But it's nothing the Universe hasn't already seen, and survived.
No civilization, no matter how successful, can last forever. What does the non-detection of intelligent aliens mean for our own longevity?
The discovery of CDG-2, a galaxy that's more than 99.9% dark matter, could reveal a new population of ultra-faint galaxies. But is it real?
No human has ever left the Solar System, and only six already-launched spacecraft will ever exit it. Will Voyager 1 remain the most distant?
Quantum entanglement links information between particles across space and time. So what happens when one of them falls into a black hole?
Forget about the terawatt lasers we're making on Earth. The Universe makes natural ones thousands of times more powerful than the Sun.
Even space and time are relative in Einstein's universe. That means our old notions of "where" and "when" no longer apply on cosmic scales.
There are plenty of engineering obstacles, and those can be overcome. But you cannot change the laws of physics, and those matter too.
The fundamental building blocks of reality are indivisible: quanta that cannot be split or divided. Our understanding remains incomplete.
Long after the last star burns out, the Universe will experience its end state: a heat death. Will everything prior then be meaningless?