The Fact Ledger

Pigs can get painful sunburns because their skin is very sensitive to the sun.

Pigs have very little hair to block sunlight. They roll in mud to create a thick layer that acts like a natural sunscreen.

Diamonds and pencil lead are made of the exact same ingredient: carbon.

The only difference is how the carbon atoms are stacked. Diamonds have atoms locked in a strong 3D shape, while pencil lead has atoms in flat layers that slide apart.

Cows have one stomach with four separate sections rather than four individual stomachs.

These sections are called the rumen, reticulum, omasum, and abomasum. They work together to turn tough grass into energy.

Your brain is more active while you sleep than when you watch television.

During a stage called REM sleep, your brain works hard to organize memories and manage emotions. This high level of activity makes your dreams feel real and vivid.

Thousands of pet rabbits once attacked and chased Emperor Napoleon Bonaparte during a hunt in 1807.

Napoleon's staff gathered about 3,000 rabbits for a celebration. These rabbits were tame and thought the Emperor was going to feed them, so they swarmed him instead of running away...

Venus is the hottest planet in our solar system because its thick atmosphere traps heat like a giant greenhouse.

The atmosphere is mostly carbon dioxide gas. This gas acts like a heavy blanket that lets sunlight in but stops heat from leaving. This makes the surface hot enough to melt lead.

The Aztecs and Mayans used chocolate beans as money to buy food and pay taxes.

Cacao beans were valuable because they were rare and could be turned into a special drink. People used them like coins to pay for goods and services.

The human liver can grow back to its full size from just one-quarter of its original mass.

Existing liver cells divide quickly to replace the missing tissue. This ability protects the body because the liver constantly filters harmful chemicals that can cause damage.

A Venus flytrap can live for 20 to 30 years in the wild.

Most small plants die after one year. This plant uses an underground stem to store energy and regrow every spring. It survives for decades by resting during the winter.

The Arkadiko Bridge in Greece is over 3,300 years old and is still used by people today.

Ancient Greeks built the bridge around 1300 BCE using massive limestone boulders. They did not use any mortar or cement to hold the stones together. It was originally made so chari...

Ketchup started as a fermented fish sauce from China called ke-tsiap.

British sailors found this salty sauce in Southeast Asia during the 1600s and took it home. People later changed the recipe by adding mushrooms, walnuts, and eventually tomatoes. T...

The first webcam was invented in 1991 to check if a coffee pot was empty.

Researchers at the University of Cambridge were tired of walking to the breakroom and finding no coffee. They set up a camera to send live pictures of the pot to their computer scr...

Flamingos are born with gray feathers and turn pink because of the food they eat.

Their diet consists of brine shrimp and algae. These foods contain natural dyes called carotenoids. The flamingo's body processes these dyes and sends them to its feathers, skin, a...

Brazilian pizzas often feature green peas, corn, and hearts of palm as standard toppings.

Local cooks use these ingredients to create different textures and flavors. They often add a popular local creamy cheese called Catupiry to the pizza as well.

George Washington's dentures were made of hippopotamus ivory, gold, and human teeth instead of wood.

Washington lost almost all his teeth by age 57. He used dentures held together by metal springs that forced his mouth open unless he actively bit down.

A day on Mars lasts 24 hours, 39 minutes, and 35 seconds.

Mars spins on its axis at nearly the same speed as Earth. This makes a Martian day, called a sol, only about 40 minutes longer than an Earth day.

The Titanic had an older sister ship called the Olympic that looked almost exactly like it and sailed for 24 years.

The Olympic was the first of three giant ships built to be the most luxurious in the world. While the Titanic sank on its first trip, the Olympic completed hundreds of successful j...

The first skyscraper used a metal skeleton to stand 10 stories tall in 1884.

Before this, tall buildings needed thick stone walls to stay up. Architect William Le Baron Jenney used a steel and iron frame to hold the weight instead of the walls.

A single pineapple plant takes up to two years to grow just one fruit.

The plant must grow dozens of leaves and a strong root system before it can produce a flower. This flower eventually develops into the pineapple we eat.

Outer space is not empty; it is filled with a thin soup of gas, dust, and radiation.

A perfect vacuum contains nothing at all. Space contains stray atoms and energy left over from the beginning of the universe. Even the emptiest parts of space have about one atom i...

Antarctica is the largest desert on Earth and is nearly twice the size of Australia.

Deserts are defined by how little rain or snow they get, not by how hot they are. Antarctica is the driest continent because its interior receives less than 2 inches of water per y...

The song 'You Suffer' by Napalm Death is the shortest song ever recorded, lasting only 1.316 seconds.

The song contains only four words: 'You suffer, but why?'. The band wrote it to mock the idea that songs need to be long or complicated.

The Statue of Liberty was an official lighthouse for 16 years.

President Grover Cleveland designated the statue as a navigational aid in 1886. It was the first lighthouse in the United States to use electricity. The light was eventually shut d...

White chocolate is not technically chocolate because it contains no cocoa solids.

Cocoa solids give chocolate its brown color and deep flavor. White chocolate uses cocoa butter instead, which is just the fat from the bean.

High heels were originally created for Persian soldiers to help them stay on their horses.

The heels locked into stirrups so riders could stand up and shoot arrows without slipping. This footwear was a tool for war long before it became a fashion choice.

The clouds on Uranus smell like rotten eggs.

The planet's upper atmosphere contains a gas called hydrogen sulfide. This is the same chemical that makes spoiled eggs and flatulence smell bad.

Hyperion is a coast redwood in California that stands 380.1 feet tall, making it the tallest living tree on Earth.

The tree grows in a secret spot in Redwood National Park to keep it safe. If too many people walk near it, they pack the soil down and damage its shallow roots.

The human body contains enough iron to make a metal nail 3 inches (7.5 cm) long.

An average adult has about 3 to 4 grams of iron in their body. Most of this metal is inside red blood cells, where it helps carry oxygen to your organs.

Sunsets on Mars look blue, while the daytime sky is a pinkish-red color.

Fine dust in the Martian atmosphere scatters light differently than the air on Earth. This dust blocks red light near the sun at sunset and lets blue light pass through to your eye...

Ancient Romans used human urine to wash their clothes.

Urine contains ammonia, which is a natural cleaner that breaks down grease and stains. Roman laundry workers collected urine from public toilets and used it to whiten woolen togas.

Bottlenose dolphins have unique names for each other called signature whistles.

Each dolphin creates its own special sound during its first year of life. They use these sounds to identify themselves and call out to specific friends or family members.

A group of giraffes standing still is called a tower.

When giraffes move together, the group is called a journey instead. Their height helps them see predators from far away. Standing in a group allows them to watch in every direction...

Smiling can make you feel happier even if you are faking it.

Moving your facial muscles into a smile sends a signal to your brain. Your brain then releases chemicals that improve your mood and lower stress.

Ruth Wakefield invented the chocolate chip cookie in 1938 when she added broken chocolate pieces to dough, expecting them to melt.

She ran out of baker's chocolate and used a Nestlé semi-sweet bar instead. The chocolate chunks stayed solid instead of mixing into the dough, creating the first chocolate chip coo...

Energy cannot be created or destroyed, only changed from one form to another.

The total amount of energy in the universe always stays the same. A car engine does not make new energy. It turns the chemical energy stored in fuel into heat and movement.

The first permanent movie theater opened in Pittsburgh in 1905 and cost only five cents to enter.

Before this, people watched movies at traveling carnivals or temporary shops. This theater was so popular that it proved movies could be a successful full-time business.

"I am" is the shortest complete sentence in English that includes both a subject and a verb.

A complete sentence needs a person or thing doing an action. In this sentence, "I" is the person and "am" is the action. Other short sentences like "Go!" are shorter but do not nam...

Ancient civilizations used water clocks to tell time by measuring the steady flow of liquid into or out of a container.

These devices used gravity to pull water through a small hole at a constant speed. People tracked the time by looking at marks on the container that showed how much water had moved...

Pluto has not finished a single orbit around the Sun since humans discovered it in 1930.

It takes Pluto 248 Earth years to complete one full trip. Because it is so far away, it moves slowly and has a very long path to travel.

Ray Tomlinson sent the first email between two different computers in 1971 and chose the '@' symbol to separate the username from the computer name.

Before this, people could only leave messages for others using the exact same computer. Tomlinson used a network called ARPANET to move digital messages from one machine to another...

A group of sharks is called a shiver.

Most sharks hunt alone, but they sometimes gather in large groups to eat, mate, or migrate. These groups can include hundreds or even thousands of sharks in one area.

Strawberries contain more Vitamin C than oranges when comparing equal weights.

One hundred grams of strawberries have about 58.8 milligrams of Vitamin C. The same weight of oranges has about 53.2 milligrams. Eating eight large strawberries gives an adult thei...

You lose between 50 and 100 hairs from your head every single day.

Each hair on your head grows for a few years and then takes a break. When a hair follicle rests, the old hair falls out so a new one can grow in its place. Since you have about 100...

Ice cream was once a rare luxury that only royalty and the very wealthy could afford.

Before refrigerators existed, people had to harvest ice from frozen lakes in the winter. They stored it in deep underground pits to keep it from melting until summer. This process...

A single banana is called a finger, and a small cluster of them is called a hand.

A large group of bananas growing on a plant is called a bunch. One bunch can hold up to 20 hands, which means it can have 200 individual fingers.

Chuck Norris was born with the name Carlos Ray Norris.

He received the nickname Chuck while serving in the United States Air Force. He kept the name when he started his career as a martial artist and actor.

Chuck Norris has written several New York Times bestselling books.

He is known for martial arts and acting but is also a successful author. He has written his life story, novels, and books about his personal beliefs.

The famous fight between Bruce Lee and Chuck Norris in the movie Way of the Dragon was filmed in a studio, not the Roman Colosseum.

Italian laws prevented the crew from filming a long fight scene inside the real Colosseum. The filmmakers took photos of the landmark and built a matching set at a studio in Hong K...

Chuck Norris started a program that teaches karate in middle schools to help kids build character.

The program is called Kickstart Kids. It uses martial arts to teach students discipline and respect during their regular school day. This helps them stay away from trouble and focu...

Chuck Norris started learning martial arts while working as a police officer for the U.S. Air Force in South Korea.

He was stationed at Osan Air Base in 1958 and found the physical training difficult. He began practicing a local style called Tang Soo Do to get stronger and more disciplined.