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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: Can someone possibly see the edge of spacetime?
Our Big Bang could be just one region within an infinite, inflating multiverse. If we were born close to the cosmic edge, what would we see?
Seven years ago, an outburst in a distant galaxy brightened and faded away. Afterward, a new supermassive black hole jet emerged, but how?
Here in our Universe, stars shine brightly, providing light and heat to planets, moons, and more. But some objects get even hotter, by far.
Most stars shine with properties, like brightness, that barely change at all with time. The ones that do vary help us unlock the Universe.
The electromagnetic force can be attractive, repulsive, or "bendy," but is always mediated by the photon. How does one particle do it all?
Many of us look at black holes as cosmic vacuum cleaners: sucking in everything in their vicinity. But it turns out they don't suck at all.
There's no upper limit to how massive galaxies or black holes can be, but the most massive known star is only ~260 solar masses. Here's why.
In the year 2000, physicists created a list of the ten most important unsolved problems in their field. 25 years later, here's where we are.
We see objects whose light only arrives just now. But we see them as they were in the past: when that now-arriving light was first emitted.
Our Universe isn't just expanding, the expansion is accelerating. Instead of dark energy, could a "lumpy" Universe be at fault?
Despite the Sun's high core temperatures, atomic nuclei repel each other too strongly to fuse together. Good thing for quantum physics!
It's simpler, more compact, and reusable from year-to-year in a way that no other calendar is. Here's both how it works and how to use it.
On larger and larger scales, many of the same structures we see at small ones repeat themselves. Do we live in a fractal Universe?
It's not only the gravity from galaxies in a cluster that reveals dark matter, but the ejected, intracluster stars actually trace it out.
Earth is actively broadcasting and actively searching for intelligent civilizations. But could our technology even detect ourselves?
Did the Milky Way form by slowly accreting matter or by devouring its neighboring galaxies? At last, we're uncovering our own history.
Forget billions and billions. When it comes to the number of galaxies in the Universe, both theorists' and observers' estimates are too low.
Known as orphaned planets, rogue planets, or planets without parent stars, these "outliers" might be the most common type of planet overall.
Our galactic home in the cosmos — the Milky Way — is only one of trillions of galaxies within our Universe. Is one of them truly our "twin?"
Electromagnetism, both nuclear forces, and even the Higgs force are mediated by known bosons. What about gravity? Does it require gravitons?
When three wise men gifted baby Jesus with gold, frankincense, and myrrh, they had no idea one was made from colliding neutron stars.