Do you know about snow? ❄️

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Speaker 1: Hi, science fans. Guess what. We are launching season four of sleep Tight Science this September, and we need your help to make it extra special. Did you know that your voice can be part of our show. We want to hear your amazing voices in our show opening. It's super easy and fun to join in. Just record yourself saying you are listening to sleep Tight Science. Then send your recording to the email address in our show notes. How cool is that. We can't wait to hear all your fantastic voices. Thank you for listening. You're listening to sleep Tight Science. You know that snowflakes can be really, really big. The largest snowflake ever recorded was a whopping thirty eight centimeters or fifteen inches wide and twenty centimeters or eight inches thick. What imagine a snowflake the size of a large pizza falling from the sky. Now that's a snowstorm you wouldn't forget. Hello, friends, and welcome back to Sleeptight Science, a bedtime show that answers your questions about science. In this episode, we will start talking about snow. Some of you might have no snow where you live, or if you in a place similar to ours. You will have a lot. There is so much snow that you can do fun things like make snow forks, snow sculptures, or throw snowballs at each other. You can also do fun activities like snowshoeing, skiing, tobogganing, or skating, though you don't skate on snow, you skate on ice. You can also make snow angels, which is fun. With all this white stuff around us, we thought it would be fun to answer some of your questions about this cold, powdery fluff. So what exactly is snow? In simple terms, snow is frozen water. Rain and snow are two forms of water that fall to the earth from the sky. The water what they supply is vital for the survival and growth of plants and animals. Water that drops from clouds is called precipitation. In one form of precipitation, rain drops form in clouds when air currents cause tiny droplets of water to collide. These droplets join together to form larger drops that fall as rain. The air must be humid for rain to reach the ground without evaporating, so this type of formation happens mainly in tropical regions. Most rain begins as ice crystals In high cold clouds. These crystals grow as water vapor freezes onto them. Whether they fall as rain or snow depends on the freezing level, the height at which water turns to ice. If the freezing level is below one thousand feet, the crystals fall as snow, not having enough time to melt. In warmer conditions with a higher freezing level, they transform into rain before reaching the ground. Did you know that snow can actually be colorful. While we usually think of snow as white, it can sometimes appear in different colors like pink, orange, or green. This happens when tiny algae that live in the snow grow and multiply, coloring the snow with their natural pigments. One of the most famous examples is watermelon snow, which gets a pink or red tint from a type of algae that thrives in cold, snowy environments. So next time you're out in the snow, remember it's not just a winter wonderland. It could be a rainbow colored wonderland too. So snow forms up in the clouds when the temperature up there is below freezing. When water vapor in the clouds cools down, it becomes ice crystals. When these tiny ice crystals stick together, they become snowflakes, and when they get heavy enough, they fall to the ground as snow now. The journey of a snowflake from the cloud to the ground is pretty interesting. The temperature and moisture in the air it falls through can change how the snowflake looks and how the snow piles up when it hits the ground. Sometimes the snow is light and fluffy, which is great for tobogganing. Other times it's wet and heavy, perfect for building a fort or a snow sculpture. But where does all this snow come from. It all starts with the water cycle, our planet's awesome system of moving water around. The Sun heats up water in the oceans, lakes, and rivers, and it turns into vapor and rises into the sky. This vapor cools down in the atmosphere and forms clouds. When it gets cold enough, we get snow. This process is happening all the time all over the world. Snow is an essential part of our planet's system. It affects how much water is available in many areas, especially places that rely on snow melt for their water. Supply. Mountains with lots of snow can act like giant frozen reservoirs. When spring comes, the snow melts and runs into rivers and streams, providing water for people, animals, and plants. Did you know that snow plays a big role in controlling the temperature of our planet. Snow is really good at reflecting sunlight, which helps keep the Earth's temperature in balance. This is called the albedo effect. Places with a lot of snow and ice, like the Arctic and Antarctic, are super important in regulating our global climate. But snow isn't the same everywhere. Depending on where you are in the world, snow can be different In some places rare and exciting event. In others, it's a regular part of life for many months of the year. The amount and type of snow can vary a lot, even from one town to the next. When we lived in Asia, we hadn't seen snow in years, and when we finally did, it was really exciting. Snow can be a lot of fun, but it can also be dangerous. Big snowstorms can make travel difficult and sometimes even knock out power, and in mountainous areas there's the risk of avalanches. That's when a large amount of snow suddenly slides down a mountain. So it's important to be safe and prepared for snow. A lot of science is involved in predicting when and where it will snow. Meteorologists use all sorts of tools and data to forecast the weather, including snow. They look at air temperatures, moisture levels, wind patterns, and more to predict snowstorms. This helps people get ready and stay safe. So that's a little bit about snow. Now let's understand a little bit about the science of snowflakes. Snowflakes are tiny masterpieces of nature, each one unique and incredibly intricate. As we mentioned, snowflakes start their life high up in the clouds, where the air is super cold. When the temperature up there dips below freezing water, vapor starts to turn into ice. But it doesn't just freeze into any old lump of ice. It forms a crystal. This happens because water molecules like to stick together in a specific pattern. Think of it like a building with a set of blocks that only fit together in certain ways. Most snowflakes have six sides or points. This is because of the way water molecules bond together. Each water molecule is like a tiny magnet with two hydrogen atoms and one oxygen atom. When they get cold enough, they line up in a hexagonal or six sided pattern. This hexagonal shape is like the blueprint for every snowflake. As the snowflake starts to fall to the ground, keeps bumping into more water vapor. This makes the snowflake grow, forming new patterns and branches. The temperature and humidity it passes through on its way down can change how the snowflake looks. That's why no two snowflakes are exactly the same. Even snowflakes that start the same way can look totally different by the time they land on your hand. The design of a snowflake is influenced by the temperature. At warmer temperatures just below zero degree celsius, snowflakes might form simple shapes like needles or hollow columns. When it gets colder around minus fifteen degrees celsius, they start to look more like the classic snowflake shape with intricate branching arms. Super Cold conditions below minus thirty deg grease celsius can make plate like or column shaped snowflakes. Humidity, which is how much water vapor is in the air, also plays a part in designing a snowflake. Low humidity means simpler shapes, while high humidity leads to more complex, detailed snowflakes. Think of it like the air being a workshop where snowflakes get more decorations if it's full of water vapor. If you ever look at snowflakes under a microscope, you will see their amazing designs. There are stars, plates, columns, needles, and even some shapes that look like tiny icy ferns. Each pattern tells a story about the snowflake's journey through the cloud and down to Earth. Even though we think think of snowflakes as white, they're actually clear. Snowflakes are made of ice, and ice is transparent, But because snowflakes have so many surfaces and angles, they scatter the light in all directions, which makes them appear white to our eyes. One of the most amazing things about snowflakes is their symmetry. The arms of a snowflake are usually mirror images of each other. This symmetry is all thanks to the way water molecules bond together it's like nature's own version of art. Now for some questions from our listeners. Our first question is from Viihan, who is seven and a half years old and lives in Dublin. The Han asks why do reindeer antlers fall off? Reindeer are special because boys called bucks and girls called dose can grow antlers. Their antlers are like big branching bones on their heads, and they grow them every year. Here's why they fall off. Reindeer grow antlers to look strong and impressive, especially during the mating season when reindeer are looking for a partner. The antlers also help them protect themselves and show off to other reindeer. Once the mating season is over, the reindeer don't need their big antlers anymore, so their bodies start to make less of a special bone strengthening chemical. Without this chemical, part where the antlers attached to their heads gets weaker. Eventually, the antlers get so loose that they fall off. But it doesn't hurt the reindeer when their antlers fall off. It's just like when you lose a baby tooth and a new one grows in. After the antlers fall off, the reindeer will start growing a new set of antlers for the next year. So reindeer antlers falling off is a natural part of their life cycle. Thank you for the question, Beahan. Next, we have a question from Heidi, who is four and from New Jersey. Heidi asks how are raindrops made? Remember when we talked about snow and how it forms in the clouds. Well, rain drops are made in a similar way, but instead of turning into snow, they stay as water like snowflakes. Rain Drops start as tiny water droplets or ice crystals in the clouds, but instead of staying frozen, these droplets get bigger and turn into rain. They do this by bumping into each other and sticking together. This can happen in two ways. In cold clouds. Up high in the clouds, where it's freezing, the droplets can freeze into ice crystals. These crystals then bump into each other, stick together, and get heavier. If it's warm enough near the ground, these ice crystals will melt into water as they fall, turning into rain drops in warmer clouds. In warmer clouds, the tiny water droplets bump into each other and join together without freezing. As more droplets join, they become bigger, and heavier, eventually growing into rain drops. So, just like with snowflakes, it's all about those tiny water droplets in the clouds getting bigger. When they're heavy enough, gravity pulls them down to us as rain drops. Thank you for the question, Heidi. Did you know that rain drops don't actually look like the tear shaped drops we often see in cartoons and drawings. In reality, rain drops are shaped more like hamburger buns. When a rain drop falls, it starts out round, but as it travels down through the air, the bottom part gets a bit flattered due to the air pushing up against it. So the next time you're out in the rain, think of the rain drops as tiny hamburgers falling from the sky. Our next question comes from Micah, who is four years old and from Colorado. Micah asks how many people are there on Earth? According to the World Population Clock, there are currently over eight billion, fourteen million people on Earth. The top five countries by population are China, India, the United States, Indonesia, and Pakistan. Now, if you tried to count all the people in the world, it would take you a really, really long time, like longer than your whole life. This is especially true because one person is being born every nine seconds. Thank you for the question, Micah. Our last question comes from Savannah, who is eight years old and from Birmingham, UK. Savannah asks why does look darker than Uranus. Neptune and Uranus are called ice giants and they are made up of similar gases. Still, Neptune is a bit different because of something called methane. Methane is a gas that's also found here on Earth, like in cowfarths. Now, both Neptune and Urinus have methane in their atmospheres, but Neptune has a little more. Methane is good at absorbing red light from the sun and reflecting blue light. Since Neptune has more methane, it reflects more blue light and absorbs more red light, making it look bluer and darker than Urinus. Urinus has less methane and more of a mixture of other gases, so it reflects light differently, giving it a lighter, more cyan or blue green color. Also, some other stuff might be going on in Neptune's atmosphere, like different gases and clouds that could make it look darker. Scientists are still studying these planets to learn more about them, so think of Neptune and Uranus as two big gassy balls out in space, with Neptune wearing a darker blue coat because it has more methane.

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Speaker 2: Thank you for the questions of Anna.

00:21:27
Speaker 1: In this episode, we started learning about snow, talking about what it is made of, the different colors it can be based upon what type of algae live in it. We talked about the water cycle and how important snow is for the water supply and certain places. It also helps control the temperature in places like the Arctic and Antarctic. Snow can be fun but also dangerous, sometimes causing accidents, power outages, and avalanches. We looked at the science of snowflakes and talked more about how they are created and unique. We looked at how the design of a snowflake is influenced by the temperature. We looked at why reindeers antlers fall off, how rain drops are made, how many people are on the Earth, and why Neptune looks darker than Urinus. This episode was made with questions from the Han from Dublin, Heidi from New Jersey, Mica from Colorado, and Savannah from Birmingham, UK. Thank you to Sam from Edwardsville, Illinois, Rosie age four in Virginia, Archer Adams from Winston Salem, North Carolina, Mia who is ten, Emily who was eight, and Noah who was six from Lugano, Switzerland. Anthony age ten in North Attleborough, Rebecca Jay from Scarsdale, New York, Xavier from Edmonton, Alberta who is seven and a half, Hayden age five from Westfield, Indiana, Everly who is six, and Adrian who is four and a half. We love getting your feedback on our show. If you have any feedback, please send it our way, and if you want to make sure you get all the episodes, please ask your parents to subscribe. You can find us on Apple podcasts or wherever your parents listen to podcasts. And please, if you love learning about science with us, leave us a review. It may help others find our show. If you'd like to send us your questions, please send them to Hello at sleeptightscience dot com. Sleep Tight