But Why is a show led by kids. They ask the questions and we find the answers. It’s a big interesting world out there. On But Why, we tackle topics large and small, about nature, words, even the end of the world. Know a kid with a question? Record it with a smartphone. Be sure to include your kid's first name, age, and town and send the recording to questions@butwhykids.org!

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Why do seasons change?

December 17, 2021 31:01 44.68 MB Downloads: 0

Why do seasons change? Why does it get darker earlier in the winter and why is there more daylight in the summer? Why are some seasons warm and some are cold and icy? Why do some places not have seasonal changes at all? We’re learning about solstices, equinoxes and seasons in this episode of But Why. Our guide is John O’Meara, Chief Scientist at Hawaii’s Keck Observatory. And kids around the world tell us what they like best about their favorite season.  Download our learning guides: PDF | Google Slide | Transcript The solstices are on December 21 and 22 and June 20 or 21, those are when the earth is leaning as far away from the sun or as close to the sun as it gets. Whether the solstice is your winter or summer solstice depends on whether you are in the northern or southern hemisphere. The two equinoxes - when both hemispheres are getting about the same amount of solar energy are on March 21 or 22 or September 22 or 23.  If you want to visualize the solstice, John O’Meara has an experiment. Find a ball and a flashlight. Have someone hold the flashlight; you hold the ball. Spin the ball around and around, the way the earth would rotate in a day. You can even draw a dot on the ball to mark where you are. Now lean the ball a little bit away from the light and keep spinning. Remember the earth is tilted on its axis (23.5 degrees to be exact!). Observe how the light falls differently on the dot. It forces the sunlight to be brighter on some spots and darker in others even during the day because of the way the light falls on the earth.  In some parts of the world there aren’t big seasonal changes. Those places are near the equator. The equator is a line around the middle of the earth, where the sphere is at its fattest or widest. While the poles get more or less light because of the tilt of the earth, the middle stays centered, so people near the equator have about the same length of daylight all year and don’t have as many seasonal shifts in light and temperature. The amount of sunlight in any given location makes a big impact on how cold or hot it is. But there are other factors that determine the climate (long-term weather trends) where you live, too. Differences in the landscape, global wind systems, proximity (how close or far you are) from the ocean, and precipitation patterns also determine what the seasons will feel like where you live. 

How are babies made?

December 03, 2021 23:17 33.55 MB Downloads: 0

How are babies made? We speak with Cory Silverberg, author of What Makes A Baby, for answers to questions about how we all come into the world. This is a conversation that welcomes all kinds of families as we answer questions about why babies don't hatch out of eggs, why boys have nipples, why girls have babies but boys don't and why some people look more like one parent more than the other. Later in the episode we also explore how we get our last names and how two people can have the same last name when they're not related. We made this episode with our youngest listeners in mind, but parents may want to preview this episode on their own or listen with their kids. Download our learning guides: PDF | Google Slide | Transcript "How are babies made?" - Wade, 7, Charlottesville, Va. In his book What Makes a Baby, Cory Silverberg begins by reminding kids and grownups that there are really two questions: what makes a baby in general, and then the more specific question that is unique to you--where did you come from? That's a question that only your parent or parents or the adults who love you can answer. While there are lots of ways that babies join families, some things are true for all of us. “For all humans to be born we need three things. We need to start with an egg; we need to start with a sperm; and those come from two different bodies. And then we need a third body part which is called a uterus. That's where we grow, where this tiny, tiny thing grows into a baby, which is the thing you are when you are born," Silverberg explains. Book recommendations from Cory Silverberg Books Geared to Kids 4 - 7 (ish) What Makes a Baby By Cory Silverberg and Fiona Smyth A book about where babies come from that works for every kind of family, regardless of who is in it and how the child came to be. What's the Big Secret: Talking about Sex with Girls and Boys By Laurie Krasny Brown and Marc Brown A simplified and clear introduction to reproduction, genitals, and touch. Leaves out a lot of kids and families, but better than most. Who Are You? The Kid's Guide to Gender Identity by Brook Pessin-Whedbee and Naomi Bardoff Also simplified, but a good introduction on gender identity written and illustrated for younger children. Books Geared to Kids 7 to 10 (ish) The Care and Keeping of You: The Body Book for Younger Girls By Valorie Schaefer and Josee Masse Only for girls, and not trans inclusive, but still one of the best books to cover a range of sexuality and puberty related topics. It's So Amazing! A Book about Eggs, Sperm, Birth, Babies, and Families By Robie Harris and Michael Emberly Covers reproduction including intercourse gestation and birth, with a focus on heterosexual, gender normative parents and kids. Sex Is a Funny Word By Cory Silverberg and Fiona Smyth Covers body parts, boundaries, touch, and an extensive gender section for kids and families of all identities and orientations. Stacey's Not a Girl By Colt Keo-Meier, illustrated by Jesse Yang A picture book about a kid who knows they aren't a girl, but isn't sure if they are a boy.

Do skyscrapers scrape the sky?

November 19, 2021 25:33 36.8 MB Downloads: 0

Why is the Burj Khalifa so tall? That’s what 5-year-old Simon wants to know. The Burj Khalifa is the tallest building in the world and it’s located in Dubai. 6-year-old Isabel, who lives in Dubai, visited the tower and gives us the bird’s eye view in this episode! Plus, Janny Gédéon, architecture educator and founder of ArchForKids answers lots more questions about tall buildings: How are tall buildings built? How do they stay up? Why are so many buildings squares or rectangles? How do they make buildings that are taller than cranes? Resources Architecture workshops and online learning: ArchForKids Download our learning guides: PDF | Google Slides | Transcript Why is the Burj Khalifa so tall? - Simon, 5, Chicago The Burj Khalifa is 160 stories tall. It measures over 2,716 feet tall – or if you think in metric that’s 828 meters. “If you put 450 grown ups stacked on top of each other, that would be the height of the building,” Janny Gedeon says. Architecture is the science of designing buildings. Architects consider the purpose of the building and what it will be used for and then they design that space. Square and rectangular buildings are less expensive to build, but architects do like to design buildings in interesting shapes. Check out the Lipstick Building in New York or the Gherkin in London, or the Sydney Opera House. Tall buildings are more common in cities because they allow more people to live in a smaller space. They have to build vertically to fit more people in a small area. “The footing, the space that the building takes is not that big, so they have to build up,” Janny says. The footing is like your footprint, the amount of space you take on the ground. Manhattan is built on a very strong rock, so it can support those tall buildings. Buildings stay up in much the same way humans stay up. There are footings--think of them like feet--that go into the ground. Buildings have a skeleton, called a structural frame, kind of like bones in a human. And on the outside, they have a cladding, aluminum or glass or other materials, kind of like our skin. Wind is a big consideration for architects building tall buildings. They design the buildings to sway. If buildings are too brittle they will break, they are designed to sway. Most skyscrapers get narrower toward the top. In earthquake prone areas, buildings sometimes have footings on a track so they can move. Activity Try making the tallest tower you possibly can, just using paper. (Newspaper works great if you have some newsprint lying around. But printer paper or construction paper is fine, too.) You should focus on making it strong and stable. Strong means that it can hold something. Stable means that if it’s pushed to the side it can stay upright. You can use cardboard for the base, but otherwise, see how you can do with just paper. Need a hint? Janny says to think about the ways you’d stay stable when playing sports.

How do squirrels climb trees?

November 05, 2021 29:29 42.47 MB Downloads: 0

Squirrels are everywhere. Three hundred or so species of these often adorable rodents live on every continent except Antarctica. No matter where you live, city or country you’re bound to have squirrels nearby. How much do you know about our bushy-tailed neighbors? How fast do squirrels and chipmunks run? Why do squirrels have big bushy tails? Do squirrels get sick? Why do they like nuts better than berries? How do squirrels eat acorns? How do squirrels sleep? Are squirrels nocturnal?  Answers to your squirrel questions with Ben Dantzer, scientist at University of Michigan. Plus some observational activities you can do to learn more about squirrel behavior! Download our learning guides: PDF | Google Slides | Transcript Submit your squirrel observations to iNaturalist How do squirrels climb up trees? -Rachel, 5, Alabama Squirrels have long nails and they have five digits (fingers or toes) on their paws just like us.  And squirrels are expert climbers. “Some tree, or arboreal, squirrels are really well adapted to climb up trees whereas ground squirrels also have nails or claws, but they use them primarily for digging and not for climbing,” explains Ben Dantzer. “Tree squirrels have this especially long middle digit that helps them climb up and down trees.” So an extra long middle finger and they can do something else that humans can’t. “The most helpful thing they can do is when they climb down a tree, squirrels can turn their back feet around when they’re climbing down head first. They turn their rear feet entirely around so they can use those claws to hang down from a tree and walk down easily.” What? Tree squirrels can turn their feet all the way around so they’re backwards when the squirrel is climbing down a tree?! Time to go outside and see if you can observe that in the wild!

Why is it a shot? Kids’ questions about COVID vaccines

October 22, 2021 29:03 41.9 MB Downloads: 0

The FDA recently gave emergency use authorization to the Pfizer-BioNTech vaccine for kids age 5 to 11. With all the news and conversation about this development, kids are curious to know more about the Covid vaccine--and vaccines in general! So in this episode we answer questions from kids and parents, including: Why does it have to be a shot? How do vaccines work? How does a vaccine trial work? Should an 11.5yo get the shot as soon as it’s available or wait until age 12 to get the larger dose? We speak with Sofia and Nico Chavez and their parents. The kids took part in the vaccine trial at Stanford University. We’re also joined by Dr. Jenna Bollyky, an investigator in the Stanford trial site, and Dr. Mark Levine, Vermont’s Health Commissioner. Download our learning guides: PDF | Google Slides | Transcript Strategies to prepare kids for shots Vaccine Info from the CDC. “Why do they have to use needles for shots?”  - Nina, 6, Maryland “In general, vaccines are a way to train your immune system without having to get sick,’ explains Dr. Bollyky Your immune system is how your body works to fight off sickness from things like viruses. Most vaccines use a small protein from the virus you want to fight, or from a similar virus – and they put that little protein in your body in a very small and weakened or changed amount to help your body learn how to fight the real invader. But giving the vaccine as a drink or a pill wouldn’t work, because of your stomach acid! “Whenever we want to give a protein or something that your body turns into a protein, the acid in the stomach does a really good job of breaking down that protein. So it’s really hard to get a vaccine that comes as a pill,” Bollyky says. “Why can’t we drink medicine to keep us safe from the virus, instead of shots? - Eloise, 5, Texas In order to get that vaccine into your muscle, where it needs to go, a doctor or a nurse uses a thin needle. They do have to poke you, but that doesn’t mean they like it. “If we could give it as a pill we would,” Dr. Bollyky promises! While that poke might hurt, sometimes the anticipation of the shot is worse than the real thing. The reason your arm sometimes aches after getting a shot is that the immune cells are coming to be educated. “The cells around where the medication was delivered, they’re doing their job, they’re taking in the information they need and are starting to train your immune system,” Dr. Bollyky assures us. “So that immune response is exactly what you want to teach your body to fight the infection should you encounter the real virus later.” It’s normal to feel a little tired or run down after some vaccines, including the COVID vaccine. But if you feel very ill, you should contact a doctor or health care provider.

How Do Apples Grow?

October 08, 2021 28:59 55.67 MB Downloads: 0

Why do apples have stems? Why do fruits start out as flowers? How did the first apple grow when no one was there to plant its seed? Why can you make a seedless grape and not a seedless apple? Why are apples so juicy? How is apple juice made? Why are apples hard and pears soft? In this episode we take a field trip to Champlain Orchards in Shoreham, Vermont to learn more about apples. Our guides are 10-year-old Rupert Suhr, his father, Bill, and apple expert Ezekiel Goodband.  Download our learning guides: PDF | Google Slide | Transcript  Flower to Fruit Image Why are some fruits a flower before they’re fruit? - Grayson, 8, San Jose, California Actually ALL fruits start as flowers (but not all flowers turn into fruit). Growing fruit is a way that some plants reproduce. Fruit is the nice ripe container that holds the seeds, which humans or animals will eat and then spread around (often through their poop), allowing new plants to grow. But that process begins with a flower. The outer part of the flower often has beautiful colors and shapes and smells—and that’s all part of the way the plant tries to attract a bee or other pollinator: “The flower has an ovary at the base of the petals. The petals are enticing a bee to come with the pollen from another blossom that it’s visited and there’s some nectar that the bee can collect and while the bee is doing that it’s shedding some pollen,” explains Ezekiel Goodband. “That pollen completes the information that the apple needs to start growing. So the flower is to attract the bee.” That ovary at the base of the flower will start to grow and that will become the apple that you eat. If you look at the bottom of an apple—the opposite end of where the stem is attached to the tree—you can actually see where the flower used to be. It even kind of looks a little bit like a tiny flower.

How Deep Is The Ocean?

September 24, 2021 19:18 18.55 MB Downloads: 0

We’re exploring a part of the world that not much is known about—in fact, you could be one of the people who help us understand and learn more about this very important, and very large, part of our earth. The land underneath the ocean is as varied and interesting as the terrain up on dry land—with mountains and canyons, plains and forests. (That’s right, forests! There are kelp forests where the kelp is as much as 150 feet tall!) In this episode, what’s known--and unknown--about the bottom of the ocean. How deep IS the deepest part of the ocean? And how was the Mariana Trench formed? We get answers from Jamie McMichael-Phillips and Vicki Ferrini of Seabed 2030, a global collaboration designed to map the sea floor, by 2030. Resources Download our learning guides: PDF | Google Slide | Transcript Seabed 2030  Visual: What Lurks In The Depths Of the Ocean? (CBC Kids) “How deep is the deepest part of the ocean?” –Freya, 8, Wellington, New Zealand The deepest part of the ocean is the Challenger Deep, 11,034 meters in the Mariana Trench. It’s about seven miles deep! How did the trench get so deep?  The same processes that formed canyons and mountains on dry land also formed the depths of the ocean and the islands that peek above the water. In the case of the Mariana Trench, it was formed by the process of subduction—when one tectonic plate slides under another. A tectonic plate is a gigantic piece of the earth’s crust and the next layer below that, called the upper mantle. These massive slabs of rock are constantly moving, but usually very slowly, so a lot of changes to the earth’s structure take place over a long time. But sometimes something like an earthquake can speed that process up. A trench is formed when one plate slides or melts beneath another one. The Mariana Trench is the deepest trench in the world—farther below sea level than Mount Everest, is tall!

Why Do Americans Use The Word ‘Soccer?’

September 10, 2021 12:23 23.78 MB Downloads: 0

Kala wants to know why we say soccer in the United States, when the rest of the world calls the game "football." In this episode we hear from people who make their living in the game: professional players, coaches and commentators. Download our learning guides: PDF | Google Slide | Transcript “Why is soccer called 'soccer,' instead of being called 'football?'” - Kala, Colchester, Vt. "It's an interesting question because so many people around the world play the game of football," said David Saward, now-retired men's coach at Middlebury College. "What happened with the words soccer and football goes back to the 1800s when the game was developed. There were two groups of people in Britain who got together to set the rules of two different games, one that was known as rugby football, and another that was known as association football. From those two first words: 'rugby' and 'association,' came two very separate games. Rugby was abbreviated to the word 'rugger.' And out of the word 'association' came 'soccer.' That's the root of where the two differences came." So although these days you probably won't hear many Brits calling the sport "soccer," the word actually originated there. Americans brought the nickname to the US, and as the sport became popular, soccer stuck. "When you look around the world," says Coach Saward, "there are all sorts of different forms of football: American football, Australian rules football, Gaelic football, rugby football and association football. I think for the clarity of everyone over here when we say the word football, we think of people running around with helmets and pads on; so soccer is a very clear distinction."

Who Invented Money?

August 27, 2021 21:55 42.09 MB Downloads: 0

In this episode of But Why we visit a credit union to learn what money is all about. And Felix Salmon, Anna Szymanski and Jordan Weissman from Slate Money answer questions about why money plays such a big role in modern society. How was money invented? Why can't everything be free? How do you earn money? How was the penny invented? Why are dimes so small? Download our learning guides: PDF | Google Slide | Transcript Related Episodes: What Is The Biggest Number? Resources: How To Talk To Kids About Money, Million Bazillion podcast Who invented money? - Luca, 9, Ashland, Ore. There's no first person we can point to who invented money. The idea of money has evolved as human society got more complicated. In the early days of humankind, people mostly bartered. Bartering is essentially trading. But over time people realized they needed to have a system for dealing with things when there wasn't an easy trade. If you have something I want but I don't want anything you're offering because I really need something else, how do we work it out? That's where the earliest forms of money emerged. First they were things like shells or rocks. Then pieces of clay with symbols or faces pressed into them. These things don't have much value by themselves, but if everyone agrees that they're going to use them as a symbol of value, you can trade them and start a system of payment. Eventually these objects became more formalized, turning into coins and paper dollar bills, like the ones we use today. These days there's another method of buying and selling: the credit or debit card.

What If You’re Scared To Start School?

August 13, 2021 24:42 47.44 MB Downloads: 0

Five-year-old Odin in Wyoming is about to start school and he sent us this question: If I’m terrified about kindergarten do I have to go? What should I do if I’m scared? What if kids are mean to me? In this episode, tips and suggestions from our listeners for kids returning to school, along with answers from guidance counselor Tosha Todd and National Teacher of the Year Juliana Urtubey. Download our learning guides: PDF | Google Slide | Transcript Related Episodes: Why Do We Have To Go To School? First day of school book recommendations from Tosha Todd First Day Jitters Night Before Kindergarten Miss Bindergarten Gets Ready for Kindergarten The Kissing Hand Back to school tips Make a hug button! Draw a heart on the inside of your hand. Draw a heart on your parent’s hand. Squeeze them together to charge your hug button. If you feel nervous at school, push the hug button and it will send you a hug. - Tosha Todd, school guidance counselor Keep a picture of your family in your backpack. You can share with your teacher the things your family does for fun. That will help your teacher understand your family. - Juliana Urtubey, National Teacher of the Year If you're nervous try to have fun and try to make some friends and the school year will be a lot better.-  Zoe, 10 Colorado Remind yourself that you are brave and confident. - Clarissa, 8, Ontario Get into a school routine now. Pick out your clothes the night before. Maybe pack your lunch too. - Tosha Todd When I start school I feel nervous, but when I step in I feel ok. For the first few days I play by myself. When those first few days are done, I play with others. - Julius, 8, Ontario Take a deep breath, be kind to someone and they'll be kind to you. - Zoe, 6, California Get everyone's names and if you forget them it's ok to ask again. - Lucy, Vermont Say hi to all the kids. - Ben, 6, Michigan You're going to make friends, and your mom and dad will pick you up; they're not going to leave you there forever. - Sly, 7, New York

Why Do We Wear Clothes?

July 30, 2021 24:26 46.92 MB Downloads: 0

Have you ever been threading one leg through a pair of pants in the morning and wondered…why do we wear pants anyway? Or wondered why pockets in clothing designed for girls are sometimes smaller than the pockets in clothing designed for boys? In this episode we’ll tackle your questions about clothes with fashion historian and writer Amber Butchart. Download our learning guides: PDF | Google Slides | Transcript “Why do we have to wear clothes?” - Bhakti, 9, Australia Many people think we started to wear clothes for practical reasons of warmth and protection. “We don’t have fur like other animals, so when modern humans started moving into colder parts of the world, we needed to protect ourselves somehow if it’s cold and snowy. This is one answer, that we wear clothes for protection,” said Amber Butchart. Butchart is a dress historian, author and broadcaster. She studies how the clothes we wear are connected to where we live and what kind of culture we grow up in, and what time period we’re growing up and living in. Butchart says, while the protection theory explains why we have to wear something—to cover our skin from the elements, there are a lot of other answers that help explain the style of clothes we wear, or don’t wear. These have to do with culture and society, and ideas about modesty as well. In this case modesty means what’s considered proper, broadly accepted as not being too wild or “out there.” A lot of how we dress comes down to what is considered appropriate in our current culture. “The idea is that these cultural codes built up across millennia and centuries and centuries, ideas that parts of our body should be covered up,” Butchart explained. “We have these social ideas to do with what parts of the body should and shouldn’t be on display, but we also have that combined with this need, especially in colder parts of the world, for protection from the elements.” But when it comes to fashion, what you wear communicates something about you to the outside world, and clothing has gone through many changes throughout history. Listen to the episode to learn more! Support But Why | Newsletter Sign-Up

What's the Cleverest Thing A Hippo Can Do?

July 16, 2021 16:54 32.46 MB Downloads: 0

What is the cleverest thing hippos can do? This week we’re answering seven quirky questions about animals! Why do elephants like peanuts? Why do cows put their tongues up their noses? Has anyone ever ridden a tiger? How do woodpeckers cling to trees? Why is some bird poop black and some is white? Why do people make animals like sharks and bears sound way scarier than they are? Answers from Keenan Stears of the University of California, Santa Barbara, Christine Scales of Billings Farm & Museum; shark researcher Kady Lyons and the Bird Diva Bridget Butler. Download our learning guides: PDF | Google Slide | Transcript Related Episodes: Why Do Elephants Have Trunks? Why Do Things Seem Scary In the Dark? Resources: Hippopotamus facts, Cornell Lab of Ornithology, Online Birding With Bird Diva  What is the cleverest thing a hippo can do? – Elliot, 8, England We turned to Keenan Stears of the University of California, Santa Barbara for some help with this tricky query. “The first thing that comes to mind that highlights the intelligence of hippos,” he told us, “is the ability to identify hippo friends from hippo enemies by the smell of their dung.” Dung is another word for poop. “Dominant male hippos use dung middens to mark their territories. A dung midden is a place where an animal repeatedly goes to drop their dung. The dung middens act as a way that hippos can keep track of the other hippos in the area. So when moving through the environment, hippos can sniff out areas where their hippo friends live, versus areas where their hippo enemies live and they can do all of this just by smelling the dung in middens.” Bet you didn’t think the cleverest thing hippos can do would involve poop! And just in case it wasn’t totally clear, a midden is basically a waste pile. So a dung midden is kind of like a toilet or an outhouse. It’s where the hippos go repeatedly to poop. But, as Stears told us, it also serves another purpose. While humans can’t tell their poop from someone else’s, other animals can sniff out individuals this way, and use dung or urine—pee—to mark their territories. Hippos aren’t the only animals to use dung middens this way, by the way. Rhinoceroses do this too! Other animals, like dogs, cats, rabbits and monkeys also sniff feces and urine as a way to learn about their fellow species, but they don’t always leave their “messages” in the same place. Support But Why | Newsletter Sign-Up

Why Are Fireworks Bright?

July 02, 2021 32:53 63.16 MB Downloads: 0

What are fireworks made of, why are they bright and loud, and how do people make them? And, why do Americans celebrate the 4th of July with fireworks? We learn about pyrotechnics with licensed fireworks professional John Steinberg. And David Chavez, an explosives expert at Los Alamos National Laboratory tells us how changes to the materials used in fireworks can make them better for the environment and unleash new, more vibrant colors in the night sky. We also address firework safety and how to impress your friends by knowing what kinds of metals are in the fireworks you’re watching or the sparklers you’re playing with. NOTE: We know not all kids (or adults) enjoy the noise of fireworks. We do play the sound of fireworks at the very beginning and very end of the episode. And John Steinberg offers some advice to people who dislike fireworks in the middle of the episode. Download our learning guides: PDF | Google Slide | Transcript Related episodes: Why Is Fire Orange?  and How Do You Make Paint? Resources: celebratesafely.org, Sparkler Safety Video,  Fireworks Colors Why are fireworks bright? –Dash, 4, Omaha, NE Steinberg told But Why that the brightness is the main purpose of fireworks. “You’re painting the in sky with light. It has to be bright enough to create the color and the effect you want to in the sky. Second, fireworks are explosive. You can’t be right up in front of it like a painting in an art gallery. You have to be some distance away, so the fireworks have to be bright enough for you to appreciate it,” he said. Fireworks are created by burning materials that shine brightly when burned. Those fires are very hot! “The types of things we burn in fireworks burn very brightly, and they’re chosen for those properties,” Steinberg said. Fireworks are created by a combustion in the sky – a combustion is something that burns. “You need a fuel and you need something to burn that fuel,” Chavez said. “An example of a fuel would be gasoline or wood in a fireplace. In fireworks, the fuels are the chemicals that we use to make the firework itself. The oxidizer is another chemical. When those two things burn, they burn very hot. And those high temperatures excite the coloring agents that we have in fireworks.” The coloring agents are metals. “Anytime you see red, that’s strontium. If you see a pinkish-purple, that’s potassium. Yellow is from sodium. Orange comes from calcium. The green is from barium, but now you can use boron. Blue is from copper. And these can be mixed to make other colors. “You need a really hot fire to be able to excite these atoms, to make them give off their color. But when they are that hot, it makes the colors come out really bright.” Chavez and other scientists have found ways to change the fuel source of fireworks to create less soot. Those changes also allowed them to replace barium, which can get into water sources, with boron, a greener way to create those green fireworks. Support But Why | Newsletter Sign-Up

Who Invented Noodles?

June 18, 2021 19:50 38.1 MB Downloads: 0

This week, we're revisiting one of our favorite older episodes from the past. We’re going to learn a little bit about the history of noodles--and how to make them! We’re joined by Jen Lin-Liu, author of the book On the Noodle Road: From Beijing to Rome with Pasta and Love. And we also get an exciting hand-pulled noodle demonstration from Tony Wu, who was the executive chef at M.Y. China, a restaurant in San Francisco’s Chinatown, when we originally recorded this audio in 2019. Wu can hand-pull 16,000 strands of noodles from one lump of dough in just two minutes...while blindfolded! Narrating this noodle-pulling exhibition is celebrity chef Martin Yan, who owned the restaurant. (M.Y. China closed during the pandemic.) Download our learning guides: PDF | Google Slide | Transcript | Video The first written references to noodles or pasta can be found in Chinese texts dating back about 3200 years. Author Jen Lin-Liu says it's likely that pasta developed in China and in the Middle East within a couple hundred years ago. But what likely didn't happen was the often repeated idea that Italian explorer and trader Marco Polo "discovered" noodles during his two decades traveling in east Asia and then introduced them to Italians upon his return. "Probably what happened," Lin-Liu told But Why, "was they were invented in China and they were also invented somewhere in the Middle East a little bit later, probably a few hundred years later. And there were two parallel cultures of noodles that developed separately. "And then," Lin-Liu continues, "because of the interactions between cultures later on, they started merging. So they were probably eating noodles in Italy and China at separate times and they didn't have much to do with each other at the beginning." On mobile? Click here to watch the video. As for how noodles are made, the ingredients are pretty basic: just flour and water. Sometimes eggs are used in place of water in Italian pasta. They can then be turned into noodles or pressed into different shapes. Sometimes they're filled with meat and cheese or other ingredients and turned into dumplings or tortellini or other filled-pasta shapes. Making pasta takes skill, both to get the consistency right and to make the perfect shapes. At Martin Yan's San Francisco restaurant M.Y. China, executive chef Tony Wu puts on a weekly show for diners, displaying his ability to hand-pull 16,000 strands of noodles from one lump of dough in under two minutes. Yan calles him a "human pasta machine," and we get to experience the excitement in this episode. Support But Why | Newsletter Sign-Up

Are Seeds Alive?

June 04, 2021 32:56 63.24 MB Downloads: 0

Are seeds alive? What are they made of? Here in Vermont it's planting time, and we've been getting a lot of questions about seeds from kids around the world. In this episode we'll explore the importance of preserving seed diversity with Hannes Dempewolf of the Global Crop Diversity Trust. Crop Trust manages a repository of seeds from around the world at the Global Seed Vault in Svalbard, Norway, above the Arctic Circle. Plus, ethnobotanist and Abenaki scholar Fred Wiseman shares a little bit about a project called Seeds of Renewal, which aims to find seeds traditionally grown by Abenaki people in our region and return them to cultivation. Download our learning guides: PDF | Google Slide | Transcript More Plant Episodes: How Do Big Plants Grow From Such Small Seeds? The Svalbard Global Seed Vault contains an enormous wealth of seeds from around the world. Unlike other seed banks, the vault is designed not to be used unless there are no other options in other seed banks. Seed banks are places where seeds are stored for future use in case of a disaster or crop failure, and are sometimes given out to help establish new populations of heritage or rare plants and crops. Seed banks also promote genetic diversity by keeping many varieties of seeds from many different plant species. "Are seeds alive?" - Evie, 5, Hawaii Yes, seeds are very much alive! At least the seeds that we use to grow food are alive. Seeds can die if they're not properly cared for, if they get too hot or cold or wet.  But under the right conditions, they're just dormant. "It means they're sleeping basically," Dempewolf says.  "Seeds are dormant and they need to be activated to grow. They need light to grow, along with humidity and warmth, that's the conditions that allow seeds to grow." "Different species of plants have very different kinds of seeds and different types of seeds also need very different conditions to grow. Some grow with very, very little humidity with very little wetness, and some need a lot. Some need to be submerged in you know under water for a while until they can grow. Some need to be frozen first before they can grow. Some seeds are made that they have to first be eaten by an animal and then pooped out again, so they can grow. Some grow with very, very little wetness, and some need to be submerged underwater for a while until they can grow. Some need to be frozen first before they can grow. Seeds are amazingly complex." Support But Why | Newsletter Sign-Up