EarthDate

Geothermal energy, the heat of the earth, can be found under our feet everywhere on Earth. Historically, we’ve only been able to access it in a few places, commonly in hot springs.  Much less commonly, in far fewer places, we find more intense heat, so close to the surface that it can be used to heat cities or generate electricity. That intense heat could be developed anywhere… if we could go deep...

Humans have lost most of our body hair, but the beard has stubbornly remained – though anthropologists can find no function for it. Perhaps that’s why men have been grooming it, or removing it, for thousands of years. Early cave paintings show men with smooth faces.  Archeologists have found flint ‘razors’ they may have used to shave. And shell ‘tweezers’ they may have used to pluck off their bear...

Birds have very large brains for their body size. New research is helping scientists understand how they work, and came to be. One part of a bird’s brain, the cerebellum, controls their amazing flight capabilities – their spatial awareness, allowing sudden direction changes through tree branches, or their ability to chart migration over thousands of miles. PET scans taken pre- and post-flight have...

If you believe the old cartoons, elephants are afraid of mice. But would a woolly mammoth be afraid of a woolly mouse? We may soon find out. That’s because scientists have recently used gene editing tools to tweak the mouse genetic code, adding genes from woolly mammoth DNA. The result? The woolly mouse, with long, shaggy fur and extra insulating fat. Fortunately, no tusks. The woolly mouse is the...

Rare Earth Elements, or REEs, are a group of 17 trace metals that play important roles in the electronics we rely on daily. Their properties are so unique, they’re not replaceable. But their current supply is almost completely controlled by China, which creates shortages and security challenges. So, researchers are looking for domestic sources—and have found a surprising one: coal ash. When coal i...

You may remember that opposite electrical charges attract. If a positive charge builds up, it seeks to connect to a negative charge, to reach equilibrium. This is what creates lightning. As explained in a prior episode, it’s generated by the static electricity of water vapor and ice molecules rubbing against each other. Billions and billions of molecules can produce a whopping charge. Positive and...

You may have heard that hydrogen could be a fuel of the future, with lower carbon emissions than any we’re using today. When it’s burned, it produces only water vapor and a lot of useful energy as heat. That sounds pretty good. And hydrogen is the most abundant element in the universe. That sounds good too. But nearly all hydrogen on Earth is bound up in other compounds, like water. Or natural gas...

On the east coast of the Yucatan Peninsula lie the wetlands of Belize. Swampy, hot and full of mosquitoes, these are unappealing places. But when they dry out each season, visitors noticed earthen banks that cut across the marsh. They thought these were water gathering facilities created by the Maya, who populated Belize centuries ago. Then carbon dating revealed they were at least a thousand year...

You may remember from a prior episode that some sponges can creep, very slowly, across the ocean floor. But most are stationary, or sessile, which make them seem less interesting. However, we continue to learn just how fascinating, and valuable, sponges are. There are 8,550 species, in all colors, shapes and sizes, in all depths of salt- and fresh water. They survive by filtering water through the...

What’s the rarest gemstone on Earth? Diamond? Ruby? Sapphire? Nope, none of these. It’s kyawthuite. The miners who discovered it thought nothing of it. This was in Myanmar, which produces a variety of gemstones: the Burmese ruby, sapphires, spinels, peridots and many others. They’re recovered in several ways. These miners were sifting through river gravel when they found a rough, rust-colored crys...

True to its name, the Venus Flytrap looks like it came from another planet, and it eats bugs. It may seem alien, but carnivorous plants are surprisingly common. There are 750 species, living on every continent but Antarctica. They exist wherever the soil can’t provide all the nutrients that plants need. So they look to other sources—often insects. The Venus Flytrap is the most well-known. Its “jaw...

Pause for a moment to ponder what a mummy smells like. Stinky? Musty? Dusty? What if I told you ‘woody, spicy and slightly sweet.’ Apparently, that’s what mummy archeologists and scent-expert ‘super-sniffers’ find. The discovery of an Egyptian undertaker’s 3,500-year-old workshop helped researchers understand why. When pharaohs or Egyptian nobles died, they could afford elaborate embalming rituals...

Animals evolved their colors to be sexy. But mostly, to be dangerous. Amphibians, reptiles, fish, insects, birds and even mammals sometimes use bright colors to attract mates. Think of the iridescent plumage of peacocks. Or the bright greens, yellows and oranges of a male iguana. But animals are about five times as likely to use bold color—especially red, yellow, black and white—to warn predators...

Rabies is almost 100% fatal. It can affect any warm-blooded creature and is transferred by any bodily fluid – though most commonly by a bite that passes saliva from the infected animal to the blood of another. It takes days or even months for the virus to incubate. But once active, it attacks the nervous system causing paralysis, coma and eventually death. Rabies kills 60,000 people annually world...

Cow manure. Garlic breath. Asparagus pee. What do they have in common? They all stink. And that stink comes from sulfur. Hydrogen sulfide is a very pungent gas that forms when plant matter decomposes, and gives its telltale fragrance to sewage, rotting garbage, and swamps. Sulfur dioxide – the smell of burned matches – is a gas produced when fossil fuels burn, metals are smelted, volcanoes erupt o...

As you listen to these words, you’re using energy. The radio in your car is powered by gasoline. Your EV, phone or computer runs on electricity. We rarely stop to think about the massive amounts of energy we use, 24-7-365. And we rarely think about where it comes from. But I can tell you in one word. Because all energy comes from one place: Earth. Oil, gas and coal are fossil fuels, made of ancien...

Scientists studying Ponderosa pines in a Colorado forest were interrupted by a wildfire – which led them to a surprising discovery. The researchers were investigating the trees’ photosynthesis, during which they take in CO2 through pores in their needles, called stoma. When heavy smoke from the wildfire filled the forest, the scientists had their equipment in place and operating, and witnessed som...

Imagine taking a photo of a speeding car. A fast shutter freezes the car in position but gives no idea of its speed. A slow shutter produces a blurred streak, suggesting speed but not much about position. This analogy applies to electrons. In the 1920s, German physicist Werner Heisenberg was studying them. The closer he came to measuring their positions, the less he could measure their speed. And...

Water bears are so hardy that researchers are studying them to try to advance human medicine. Scientifically they’re called tardigrades. There are over a thousand species living in wet environments, from the deep sea to moss beds in the Himalayas. They may look like bears, but there’s no relation. To begin, they’re microscopic, usually less than a millimeter in length. They have a digestive tract,...

The dark side of the moon isn’t really dark. It has a lunar day just like the near side. The far side just seems dark to us, because it faces away from Earth and we never see it. US space missions never landed there, but China was determined to explore it. So, they began a multi-decade, unmanned lunar program, named after the Chinese moon goddess, Chang’e. In 2007 and 2010, Chang’e 1 and 2 spacecr...

Earth may once have had rings, like Saturn – and all the more distant planets of our solar system. Saturn’s are just the most visible, and therefore the most famous. Rings are made of debris – from asteroids, moons, or from the formation of the planets themselves. Scientists think the rings around Saturn are the remains of one of its moons that was torn apart by the giant planet’s gravity. They th...

In the 1970s, Roger Payne had a multi-platinum record, a surprise hit for two big reasons: Payne was a marine biologist, not a musician. And the singers on the album… were whales. Payne’s “Songs of the Humpback Whale” revealed that other creatures may have complex language. It raised interest in whale intelligence, and led to the passage of laws protecting them. It also encouraged scientists from...

A million Americans listen to this show each week. Some at Earthdate.org. But the huge majority on the radio. That’s because, in our increasingly online world, radio is still the leading way people consume media. It began when an engineer named Reginald Fessenden improved on early transmitters to create a continuous stream of radio waves. In 1906, he made the first broadcast, of himself playing th...

Amber is a “gem” that’s often a window into the ancient past. For thousands of years it’s been valued for its beauty, collected by humans and formed into jewelry and other treasures. But amber is actually not a gemstone, or a mineral at all. It’s fossilized tree resin. Trees secrete resin in reaction to damage. The resin hardens like a scab to seal the injury and protect the tree from disease. But...

Sixty years ago in central Turkey, a homeowner made a remarkable discovery. When remodeling his basement, he knocked down a wall and found a tunnel. He followed the tunnel to find one of the largest underground cities in the world, abandoned long ago. When scientists explored it, they discovered it went down 18 levels, 280 feet into the ground, and was once home to some 20,000 underground dwellers...