U.S. airlines carry more than 800 million passengers per year.
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People have been flying airplanes for well over a century. Engineers know how to balance all the forces at play, but still aren’t exactly sure how some of the physics of flight actually works.
The reason trees need sunlight is the same reason their leaves are green.
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Trees – and all plants – harvest sunlight to gain the energy they need to live and grow.
The queen, on the right with a larger, darker body, is bigger than the worker bees in the colony and lives several times longer.
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A queen’s main job in the hive is to lay eggs and pass genes on to offspring. But many bee species do just fine without queens or big colonies.
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Personality is shaped by our genes and various influences in our social environments, and it plays an important role in how we interact with the world.
Some parts of the U.S. see well over 100 inches (2.5 meters) of snow per year.
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There are an infinite number of paths an ice crystal can take before you touch it.
Leap Day is coming.
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Humans have synced their calendars to the sun and moon for centuries, but every so often, these systems need a little correction.
Can you detain someone you just saw break the law?
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Stopping someone against their will can be false imprisonment or even kidnapping. There are laws that determine who is acting as a hero and who is acting as a vigilante.
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Shivering actually helps warm our bodies up.
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The interest your bank pays you is a reward for letting it use your money.
Your blood’s natural limit to how much oxygen it can hold means you can’t stockpile it.
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Inhaling air is how you get the oxygen your body needs to turn your food into energy. Other living things use different strategies.
Creating the alphabet took thousands of years.
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Turns out ‘A’ didn’t have to be the first letter in the alphabet, nor ‘Z’ the last.
The types of music you listen to can reflect your personality traits.
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Lots of factors can influence your music taste, from your age and where you’re from to the personality traits you have.
Your immune system encounters a legion of potential pathogens every day.
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Your immune system is often able to fend off pathogens it’s never seen before. But defending your body against all of them all at once is a tough challenge.
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We can look at the value of the things we buy and sell.
Fish swim in a reef at Pearl and Hermes Atoll in the Northwestern Hawaiian Islands.
AP Photo/Jacob Asher
There are so many fish in the ocean that if you took them out, important habitats and food sources for many creatures would be lost.
Black holes use gravity to pull matter into them.
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Pictures of black holes have a white outline around them when photographed, due to one of black holes’ unique and key features.
A full set is two on the top and two on the bottom.
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Two dental experts explain that these furthest-back molars may be a not-so-necessary leftover from early human evolution.
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Kian, age 6, has some interesting questions about farts that we’re probably all wondering about.
Matter in deep space is very spread out, which makes it impossible for any sound waves to travel.
NASA, ESA, CSA, STScI
Sound needs matter to propagate, so the vast vacuum of space is not just empty − it’s silent.
Spreading rumors about others is one form of bullying.
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No matter your age, if you’re being bullied − there’s help out there.