Space & Cosmos
How Do Black Holes Die? The Slow Fade of the Darkest Things
How do black holes die? Through Hawking radiation, they slowly evaporate over almost unimaginable spans of time. Here's how the universe's darkest objects end.
A library of wonder. Clear, accurate answers to the questions about space, life on Earth, and the science of you that you keep meaning to look up.
Space & Cosmos
How Big Is the Universe? (And Does It Have an Edge?)
How big is the universe? The observable universe spans 93 billion light-years, but the whole thing may be infinite. Here's what 'size' even means in space.
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Life on Earth
How Deep Is the Ocean? (And What Lives at the Very Bottom)
How deep is the ocean? The deepest point plunges nearly 7 miles down. Here's what the journey looks like, and the astonishing life waiting in the dark.
The Science of Us
What Causes Déjà Vu? The Science Behind That Eerie Feeling
What causes déjà vu, that sense you've lived this moment before? Leading brain science points to a memory 'misfire.' Here's the most likely explanation.
Space & Cosmos
For the questions that make the room feel bigger.
Space & Cosmos
Why is Pluto not a planet? The vote that demoted a world
Why is Pluto not a planet? In 2006 astronomers voted it a dwarf planet for failing one rule: it never cleared its orbit. The full story, and the man who killed it.
Space & Cosmos
Where Does Gold Come From? The Cosmic Catastrophe Behind Every Wedding Ring
Where does gold come from? The gold in your jewelry was forged in a neutron star collision billions of years ago. Here's the wild physics behind it.
Space & Cosmos
What Happens When the Sun Dies?
What happens when the sun dies? In 5 billion years it swells into a red giant, swallows the inner planets, and fades to a white dwarf. Here's the timeline.
Space & Cosmos
Why Do Stars Twinkle but Planets Don't?
Why do stars twinkle while planets shine steadily? The answer is our turbulent atmosphere bending starlight, and a surprising trick of distance and size.
Life on Earth
For nature's cleverest and most unlikely tricks.
Life on Earth
How hard does a mantis shrimp punch?
How hard does a mantis shrimp punch? Up to 1,500 newtons at 23 m/s, with cavitation bubbles that flash light and deliver a second hit. The physics, explained.
Life on Earth
The immortal jellyfish that ages in reverse
The immortal jellyfish, Turritopsis dohrnii, rewinds its own body from adult back to a baby polyp. Here is how that escape from old age actually works.
Life on Earth
Why the Deep Sea Doesn't Crush Fish: The Physics and Chemistry of Surviving the Abyss
Why deep sea pressure doesn't crush fish comes down to water, not air, and a molecule that sets a hard chemical limit on how deep any fish can go.
Life on Earth
What Would Happen to Your Body at the Bottom of the Mariana Trench?
Would the deep sea crush you flat? Not the way movies show it. Here is what nearly 16,000 psi would really do to an unprotected human body, and why.
Life on Earth
How Do Tardigrades Survive Space? Meet the Toughest Animal Alive
How do tardigrades survive space, boiling, freezing, and radiation? These microscopic 'water bears' have a survival trick that borders on the miraculous.
Life on Earth
Why Do So Many Sea Creatures Glow? Bioluminescence Explained
Why do sea creatures glow? Bioluminescence, living light from a chemical reaction, fills the deep ocean for hunting, hiding, and luring. Here's how it works.
The Science of Us
For the odd machinery behind ordinary life.
The Science of Us
Cute aggression: why you want to squeeze the puppy
Cute aggression is the urge to squeeze or playfully bite adorable things. A Yale team named it in 2013; 2018 brain scans found the cause. Here's the science.
The Science of Us
Why Do You See Faces in Things? The Brain Trick That Never Turns Off
Why do we see faces in things like outlets and car grilles? It's your brain's face detector running hot, and the science goes deeper than you'd think.
The Science of Us
Why Can't You Tickle Yourself? Your Brain Is One Step Ahead
Why can't you tickle yourself? Your cerebellum predicts your own touch and cancels the sensation before it registers. Here's the weird science behind it.
The Science of Us
Why Do We Dream? What Science Actually Knows
Why do we dream? Science has several leading theories, from memory sorting to emotional processing to threat rehearsal. Here's what we really know about dreams.
The Science of Us
Why Is the Sky Blue? (And Why It Turns Red at Sunset)
Why is the sky blue? The real answer is a story about sunlight, tiny air molecules, and a trick of physics called Rayleigh scattering, explained simply.