The most colorful gemstones on Earth - Jeff Dekofsky

What gives opals their signature shimmering colors? Dig into the science of the gemstone’s formation, millions of years in the making. -- In November 1986, Australian miners climbed Lunatic Hill and bored 20 meters into the Earth. They were rewarded with a fist-sized, record breaking gemstone, which they named the Hailey’s Comet opal. Thanks...

1d

The myth of Loki and the deadly mistletoe - Iseult Gillespie

Discover the Norse myth of Baldur, the most beloved being in Asgard, and how the trickster god Loki plotted his death. -- Baldur was the gentlest and most beloved being in all of Asgard. But lately, he had been plagued by gruesome visions foretelling his own imminent death. Determined to protect her son from these grim prophecies, Queen Frigg...

3d

Why is pneumonia so dangerous? - Eve Gaus and Vanessa Ruiz

Explore how pneumonia attacks the tiny air sacs in your lungs and how your immune system works to fight off the infection. -- Every time you breathe, air travels down the trachea, through a series of channels, and then reaches little clusters of air sacs in the lungs. These tiny sacs facilitate a crucial exchange: allowing oxygen from the air...

4d

Which bag should you use? - Luka Seamus Wright and Imogen Ellen Napper

Explore the environmental impact of three types of bags— plastic, paper, and cloth— to find out how they’re made, used and disposed of. -- You’ve filled up your cart and made it to the front of the grocery line when you’re confronted with yet another choice: what kind of bag should you use? It might seem obvious that plastic is bad for the environment,...

3w

Can you solve the Alice in Wonderland riddle? - Alex Gendler

Practice more problem-solving at https://brilliant.org/TedEd/ -- After many adventures in Wonderland, Alice has once again found herself in the court of the temperamental Queen of Hearts. She’s about to pass through the garden undetected, when she overhears the king and queen arguing that 64 is the same as 65. Can Alice prove the queen wrong...

3w

How fast is the speed of thought? - Seena Mathew

Travel into the brain to see how its network of neurons transmit your thoughts and what factors determine how quickly you think. -- Your mortal enemy has captured you and hooked you up to a bizarre experiment. He’s extended your nervous system with one very long neuron to a target about 70 meters away. At some point, he’s going to fire an arrow....

3w

Why do you get a fever when you're sick? - Christian Moro

Discover what happens in your body when you have a fever and why its role in our immune response remains a mystery to scientists. -- There are many mysteries around fever, but we do know that all mammals, some birds and even a few invertebrate and plant species feel fever’s heat. It has persisted for over 600 million years of evolution. But it...

4w

How do investors beat the stock market? - Richard Coffin

Explore the strategies investors use to choose stocks and learn whether it’s better to be an active or passive investor. -- Every day, billions of stocks are traded on the New York Stock Exchange alone. But with over 43,000 companies listed on stock exchanges around the world, how do investors decide which stocks to buy? And what do individuals...

4w

How do steroids affect your muscles— and the rest of your body? - Anees Bahji

Dig into the science of how anabolic steroids and their recreational use can affect your body, organs and brain. -- Steroids. They’ve caused global scandals. They’re banned in most athletic competitions. Yet the same properties that help elite athletes and bodybuilders improve performance also make steroids valuable for treating many illnesses...

4w

Do larger animals take longer to pee? - David L. Hu

Dive into the physics of the “Other Golden Rule” and explore the systems and methods animals use to excrete waste. -- A cat’s bladder can only store a golf ball’s worth of urine. For humans, it’s a coffee mug and for elephants, a kitchen trash can. An elephant’s bladder is 400 times the size of a cat’s, but it doesn’t take an elephant 400 times...

5w