SCIENCE

How everything around you actually works - light, heat, matter, energy, life.

51 facts

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A brainless yellow slime can solve mazes.

A brainless yellow slime can solve mazes.

Slime mold has no brain, no nerves, no eyes - but it figures out the shortest route to food.

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MORE SCIENCE FACTS

50 facts

The Moon pulls our oceans toward it twice a day.

DID YOU KNOW? The Moon pulls our oceans toward it twice a day. Tides happen because the Moon's gravity tugs water more strongly on the side of Earth nearest it. 2 min read

Life on Earth has nearly been wiped out five different times.

DID YOU KNOW? Life on Earth has nearly been wiped out five different times. Five mass extinctions have killed off most species - and life keeps coming back. 2 min read

All the ants on Earth weigh about the same as all the humans.

DID YOU KNOW? All the ants on Earth weigh about the same as all the humans. Tiny but countless - ants make up an enormous slice of life on the planet. 2 min read

Some bacteria thrive where almost nothing else can survive.

DID YOU KNOW? Some bacteria thrive where almost nothing else can survive. They live in boiling water, acid lakes, the depths of nuclear reactors. 2 min read

Metals conduct electricity because their electrons are free to roam.

DID YOU KNOW? Metals conduct electricity because their electrons are free to roam. In metal atoms, outer electrons aren't tied to any one atom - they drift through the whole structure. 2 min read

Lightning strikes the Earth about 40 times every second.

DID YOU KNOW? Lightning strikes the Earth about 40 times every second. That's roughly 3 to 4 million strikes a day, somewhere on the planet. 2 min read

Earth's days are slowly getting longer.

DID YOU KNOW? Earth's days are slowly getting longer. The Moon is gradually slowing our rotation. A day will eventually last 47 hours. 2 min read

Mount Everest grows about 4 mm taller every year.

DID YOU KNOW? Mount Everest grows about 4 mm taller every year. India is still slowly crashing into Asia, pushing the Himalayas higher. 2 min read

97% of Earth's water is in the oceans.

DID YOU KNOW? 97% of Earth's water is in the oceans. Only 3% of the planet's water is fresh - and most of that is locked in ice. 2 min read

Earth's magnetic field flips upside down every few hundred thousand years.

DID YOU KNOW? Earth's magnetic field flips upside down every few hundred thousand years. North becomes south, south becomes north, and compasses point the opposite way. 2 min read

All the continents used to be one giant supercontinent.

DID YOU KNOW? All the continents used to be one giant supercontinent. It was called Pangaea - and you can see how it fit together by looking at a map. 2 min read

The Moon used to be much closer to Earth - and is slowly drifting away.

DID YOU KNOW? The Moon used to be much closer to Earth - and is slowly drifting away. It's currently moving away from us by about an inch and a half a year. 2 min read

Earth is 4.5 billion years old.

DID YOU KNOW? Earth is 4.5 billion years old. For most of that history, no one was here to see it. 2 min read

Only about 21% of the air is oxygen.

DID YOU KNOW? Only about 21% of the air is oxygen. Most of what you breathe is nitrogen - and it does almost nothing. 2 min read

Earth's atmosphere has five distinct layers.

DID YOU KNOW? Earth's atmosphere has five distinct layers. From the ground to the edge of space, it changes character several times. 2 min read

The continents drift across Earth's surface - about an inch a year.

DID YOU KNOW? The continents drift across Earth's surface - about an inch a year. Earth's crust is broken into giant pieces that slide around like puzzle parts. 2 min read

Earth's inner core is as hot as the surface of the Sun.

DID YOU KNOW? Earth's inner core is as hot as the surface of the Sun. Right at the center of our planet, it's about 5,500°C - same as a sunny day on the Sun. 2 min read

The world's largest single living organism is a forest of aspen trees.

DID YOU KNOW? The world's largest single living organism is a forest of aspen trees. All 47,000 trees in Pando, Utah, share one giant root system. 2 min read

Humans and bananas share many of the same basic genes.

DID YOU KNOW? Humans and bananas share many of the same basic genes. All life on Earth descends from a common ancestor - and a lot of the basic genetic toolkit got carried forward. 2 min read

Eyes have independently evolved at least 50 different times.

DID YOU KNOW? Eyes have independently evolved at least 50 different times. From octopus eyes to spider eyes to your eyes - evolution invented eyesight over and over. 2 min read

Viruses aren't quite alive - and aren't quite not.

DID YOU KNOW? Viruses aren't quite alive - and aren't quite not. They have genes but can't reproduce on their own. They're life's weird middle ground. 2 min read

We can now edit DNA like a word processor.

DID YOU KNOW? We can now edit DNA like a word processor. CRISPR is a tool that lets scientists snip out one gene and replace it with another. 2 min read

Every cell in your body runs on a tiny molecule called ATP.

DID YOU KNOW? Every cell in your body runs on a tiny molecule called ATP. It's the universal energy currency of life on Earth. 2 min read

Every living thing alive today evolved from earlier forms over billions of years.

DID YOU KNOW? Every living thing alive today evolved from earlier forms over billions of years. Slow changes, generation by generation, turned bacteria into whales and ferns into oak trees. 2 min read

You have more bacterial cells in your body than human cells.

DID YOU KNOW? You have more bacterial cells in your body than human cells. There are about 38 trillion bacteria living on and inside you right now. 2 min read

Plants make food out of sunlight and air.

DID YOU KNOW? Plants make food out of sunlight and air. Photosynthesis is one of nature's most powerful tricks - and we'd starve without it. 2 min read

DNA is the instruction manual for building you.

DID YOU KNOW? DNA is the instruction manual for building you. A microscopic code, 3 billion letters long, written in every one of your cells. 2 min read

The most common element in the universe is hydrogen.

DID YOU KNOW? The most common element in the universe is hydrogen. About 75% of all the regular matter out there is just hydrogen atoms. 2 min read

All life on Earth is built from carbon.

DID YOU KNOW? All life on Earth is built from carbon. Carbon atoms link to other atoms in more ways than any other element. 2 min read

Your blood contains enough iron to make a small key.

DID YOU KNOW? Your blood contains enough iron to make a small key. Iron is what makes your blood red - and helps it carry oxygen. 2 min read

You're about 60% water.

DID YOU KNOW? You're about 60% water. An adult human is essentially a walking, talking, leaky water balloon. 2 min read

The periodic table has 118 known elements.

DID YOU KNOW? The periodic table has 118 known elements. Everything in the universe is built from this short list. 2 min read

The pH scale runs from 0 to 14 - and most of your favorite drinks are pretty acidic.

DID YOU KNOW? The pH scale runs from 0 to 14 - and most of your favorite drinks are pretty acidic. Coke has a pH of about 2.5 - almost as acidic as lemon juice. 2 min read

Diamond and pencil lead are the exact same element.

DID YOU KNOW? Diamond and pencil lead are the exact same element. Both are pure carbon. The atoms are just arranged differently. 2 min read

Helium doesn't actually change your voice - it changes how fast sound travels through it.

DID YOU KNOW? Helium doesn't actually change your voice - it changes how fast sound travels through it. Sound moves three times faster through helium than air, which makes your voice sound squeaky. 2 min read

Table salt is made of two poisonous elements.

DID YOU KNOW? Table salt is made of two poisonous elements. Sodium burns in air. Chlorine is a deadly gas. Together they season your fries. 2 min read

Water is weird - it gets bigger when it freezes.

DID YOU KNOW? Water is weird - it gets bigger when it freezes. Almost every other liquid shrinks when it cools. Water grows. 2 min read

Heat and temperature aren't the same thing.

DID YOU KNOW? Heat and temperature aren't the same thing. A spark from a sparkler is 1,800°F but won't burn you. A cup of coffee at 180°F will. 2 min read

Two particles can be linked across any distance.

DID YOU KNOW? Two particles can be linked across any distance. Measure one and you instantly know the other - even if it's on the other side of the universe. 2 min read

Electricity and magnetism are two sides of the same force.

DID YOU KNOW? Electricity and magnetism are two sides of the same force. Move a magnet through a coil of wire and you make electricity. Move electrons in a wire and you make a magnet. 2 min read

A laser is just incredibly focused, perfectly synchronized light.

DID YOU KNOW? A laser is just incredibly focused, perfectly synchronized light. Every photon in a laser beam marches in the exact same direction at the exact same wavelength. 2 min read

Glass isn't quite a normal solid - its atoms are scrambled like a liquid's.

DID YOU KNOW? Glass isn't quite a normal solid. Its atoms are scrambled like a liquid's - but frozen in place. Scientists call it an "amorphous solid". 2 min read

Friction always creates heat.

DID YOU KNOW? Friction always creates heat. Rub your hands together and that warmth is energy turning into temperature. 2 min read

For every action, there's an equal and opposite reaction.

DID YOU KNOW? For every action, there's an equal and opposite reaction. Push against a wall and the wall pushes back just as hard. 2 min read

Light is both a particle AND a wave.

DID YOU KNOW? Light is both a particle AND a wave. Depending on how you measure it, you get a different answer. 2 min read

Gravity is the weakest force in the universe.

DID YOU KNOW? Gravity is the weakest force in the universe. A tiny magnet can pick up a paperclip - beating all of Earth's gravity holding it down. 2 min read

Sound can't travel through empty space.

DID YOU KNOW? Sound can't travel through empty space. It needs air, water, or some other substance to push through. 2 min read

Light is the fastest thing in the universe.

DID YOU KNOW? Light is the fastest thing in the universe. It travels 186,000 miles per second - and nothing can go faster. 2 min read

Bananas are slightly radioactive - but totally safe to eat.

DID YOU KNOW? Bananas are slightly radioactive - but totally safe to eat. Scientists use the "banana equivalent dose" as a fun way to compare radiation levels. 2 min read

Hot water can freeze faster than cold water - and nobody knows exactly why.

DID YOU KNOW? Hot water can freeze faster than cold water - and nobody knows exactly why. It's called the Mpemba effect, and scientists are still arguing about it 60 years later. 2 min read

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