The number zero was a relatively recent and crucial addition − it allows numbers to extend in both directions forever.
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Here’s a game: Tell a friend to give you any number and you’ll return one that’s bigger. Just add ‘1’ to whatever number they come up with and you’re sure to win.
Listen to the trailer for The Conversation’s Curious Kids, a new podcast where kids get answers to their big questions from experts.
Thousands of galaxies, each containing billions of stars, are in this 2022 photo taken by the James Webb Space Telescope.
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Now out in space for more than two years, the James Webb Space Telescope is a stunningly sophisticated instrument.
The Punch Powertrain Solar Team car from Belgium competes in the 2017 World Solar Challenge near Kulgera, Australia.
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It’s common to see solar panels on rooftops and fields, but they aren’t widespread on cars − yet.
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People once used tooth powders made from crushed bone or shells to whiten their teeth. Others rinsed their mouth out with pee. Yuck!
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The most common eye colour is brown, then blue, and less often, green or hazel. But the human body only makes brown iris pigment.
Dig into soil and you’ll find rock dust but also thousands of living species.
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Rock dust is only part of the story of soil. Living creatures, many of them too tiny to see, keep that soil healthy for growing everything from food to forests.
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.