Unexplainable is a science show about everything we don’t know. Host Noam Hassenfeld is joined by an array of experts and Vox reporters each week to look at the most fascinating unanswered questions in science and the mind-bending ways scientists are trying to answer them. New episodes drop every Wednesday. From Vox and the Vox Media Podcast Network.

Life Sciences
Natural Sciences
Can ovaries make new eggs?
There's an old story scientists tell about human ovaries: that they are ticking clocks that only lose eggs, never gain them.
26 min
Will the eel (slim, shady) please have sex?
Where eels come from is a surprisingly difficult question to answer, in large part because scientists have never actually seen them reproduce in the wild.
44 min
Yawn baby yawn
People yawn when they’re bored, right?
34 min
What’s the James Webb telescope searching for?
A lava planet, life on other worlds, the very first starlight in the universe — the most powerful space telescope ever built is ready to reveal many mysteries of the cosmos.
46 min
Vitamin X
Millions of Americans take dietary supplements — everything from vitamins and minerals to weight loss pills and probiotics.
31 min
Lost Worlds: What killed Venus?
Venus is the hottest, scariest place in the solar system, but billions of years ago it may have been a lot like Earth, complete with an ocean of water.
25 min
Lost Worlds: Life on Mars?
Mars was once a very different planet, with rivers, lakes, and — potentially — life.
27 min
Lost Worlds: Why do we have a moon?
In all our searching of the universe, we’ve never seen another moon like ours.
24 min
Lost Worlds: Aliens from Earth?
Was there a technologically advanced species living on Earth long before humans?
24 min
Dropping like flies
Insect populations are shrinking all over the world
24 min
Is telepathy real?
A groundbreaking study claims to have found a way for a fully paralyzed person to communicate entirely via thought. Today, Explained breaks down the science and asks: Is it too good to be true?
23 min
Why do we dream?
Dreams are weird, but can they be a scientific tool?
20 min
Should I take a DNA ancestry test?
What are the scientific, family, and privacy implications?
25 min
My octopus friend?
Octopuses are largely solitary animals, but there have been rare times — notably in the movie My Octopus Teacher — where they seem to have become comfortable around humans
22 min
Glow in the dark ocean
Most deep-water creatures are bioluminescent. Marine biologist Edie Widder has spent the last 40 years trying to figure out why.
28 min
When reality broke
In the 1920s, the scientist Werner Heisenberg came up with a wild idea that broke reality as Western science knew it.
23 min
Making Sense: The sixth sense
Why stop at five senses?
24 min
Making Sense: Sight unseen
Close your eyes and try to imagine an apple. Can you see anything?
22 min
Making Sense: The Umami Mama
For thousands of years, there have been four basic tastes recognized across cultures.
34 min
Making Sense: No one nose
26 min
Making Sense: The healing power of touch
Doctors can save the lives of premature infants, but the process is often painful. Luckily, a solution might be as simple as a parent’s loving touch.
25 min
Making Sense: How sound becomes hearing
In the same way optical illusions trick our eyes, audio illusions can trick our ears.
37 min
The methane hunters
Methane traps more than 80 times as much heat as CO2 over the short term.
20 min
What is love?
Can science help us predict whether a relationship will succeed? Or is it all just chaos?
30 min
A sonic tour of the solar system
What does it sound like on Mars? On Jupiter? Titan?
19 min
Finding asteroids before they find us
Scientists are constantly searching for asteroids that could crash into Earth.
28 min
Skeleton Lake
When scientists examined the DNA of ancient bones found near a Himalayan lake, they were forced to confront a seemingly impossible conclusion.
25 min
Are humans running out of sperm?
In 2017, researchers published an explosive finding: Sperm counts may be declining in some countries around the world.
25 min
The quest to build a star
Scientists are closer than ever to harnessing fusion power — the same process that powers the sun — by essentially making a small star here on Earth.
25 min
BONUS: The 2021 song
Noam wrote an end-of-year song with Today, Explained host Sean Rameswaram, so we thought to drop it here as a little end-of-year surprise.
5 min
The building blocks of the universe
Most of the matter in the universe is dark matter, an invisible, untouchable, mysterious substance. Scientists don’t know what exactly dark matter is, despite decades of searching. But recently, they got a new clue in the form of an extremely tiny dancer.
51 min
99% of ocean plastic is missing
How can we solve the problem of ocean plastic if we don’t know where most of the plastic is?
27 min
How medicine mansplained women’s health
Until 1993, many researchers excluded women from clinical drug trials, leaving doctors in the dark about how new treatments work in more than half the population.
23 min
How Venus went to hell
Venus is the hottest, scariest place in the solar system, but billions of years ago it may have been a lot like Earth, complete with an ocean of water.
24 min
Mind readers
Will scientists ever fully understand the human brain?
29 min
A brainless yellow goo that does math
Slime molds can navigate mazes, control robots, and make complicated decisions, all without a central nervous system.
22 min
Why whales get beached
Every year, thousands of marine mammals end up trapped on beaches, but it’s often hard to figure out why.
19 min
Talking to ghosts
Why do so many people think they can see and hear ghosts, and what does that say about our conscious experience of the world?
29 min
Honey, we shrunk the birds
A recent study of tens of thousands of birds has shown that birds are growing smaller over time.
24 min
Nobel Prize 2.0
The Nobel Prize has rewarded some amazing discoveries.
23 min
The James Webb Time Machine
To look into deep space is to look back in time.
26 min
The James Webb Space Telescope
After decades of planning, NASA is finally (finally!) set to launch the successor to the Hubble.
23 min
What causes Alzheimer’s?
For decades, Alzheimer’s researchers have been stubbornly pursuing a single theory, but they’re starting to wonder: is this narrow focus the reason we still don’t have a cure?
27 min
Havana syndrome
Several years after US diplomats in Cuba claimed they were attacked by an invisible weapon, similar incidents continue to be reported around the world.
25 min
Getting to the bottom of butts
Once upon a time, there were no anuses.
23 min
The mysteries of endometriosis
This common chronic condition — where tissue that normally grows in the uterus grows elsewhere in the body — is barely understood.
27 min
A 150-year-old human
Two scientists. A billion-dollar wager. One unanswered question: Is the first human who will live to 150 already alive?
27 min
How low can you go?
Earlier this year, Nicole Yamase explored the bottom of the Challenger Deep, the deepest place in the ocean, where few people have ever been.
25 min
The tornado problem
8 minutes, 24 seconds.
21 min
Moon poop
Astronauts left something on the moon that could help unlock the origins of life itself.
21 min
Hot pink flying squirrels
An accidental discovery on a nighttime walk led one scientist and his team to wonder: How many mammals glow under ultraviolet light?
27 min
Henrietta Leavitt and the end of the universe
In the early 1900s, Henrietta Leavitt made one of the most important discoveries in the history of astronomy: a yardstick to measure distances to faraway stars.
28 min
How do animals know where to go?
25 min
Invasion of the jumping worms
These worms are fast, they’re mysterious, and they’re quickly changing North American ecosystems.
23 min
The many heights of Mount Everest
How tall is the world’s tallest mountain?
26 min
Unexplainable Flying Objects
UFOs are real, but that doesn’t mean they’re aliens.
29 min
The hunt for a new Pluto
Something strange is going on at the outer reaches of the solar system.
30 min
Cloudy with a chance of chaos
It’s surprisingly hard to predict how clouds form, move, and change.
25 min
A new force of nature?
Last month, physicists at Fermilab in Illinois found that tiny subatomic particles called muons were wobbling strangely.
22 min
Placebos work. Why?
For decades, scientists thought that placebos only worked if patients didn’t know they were taking them.
23 min
A virus that could heal people
In 2016, the UN declared antibiotic-resistant bacteria the “greatest and most urgent global risk.” Our best hope just might be phages,
21 min
The Twilight Zone of the ocean
A dive into its mysterious depths
24 min
The viral ghosts of long Covid
Scientists don’t understand why so many people suffer from Covid-19 symptoms for months, long after they stop testing positive.
22 min
Is a ton of psychology just ... wrong?
27 min
It’s ball lightning!
A perfect sphere of crackling light
23 min
Skeleton Lake
When scientists examined the DNA of ancient bones found near a Himalayan lake, they were forced to confront a seemingly impossible conclusion.
25 min
Journey Toward the Center of the Earth
What lies beneath our feet?
25 min
No one nose
Believe it or not, scientists still don't know how the sense of smell works.
26 min
Most of the universe is missing
Scientists all over the world are searching for dark matter: an invisible, untouchable substance that holds our universe together.
30 min
Introducing Unexplainable
2 min