A short message for grownups.
Holiday travel with little ones can be an adventure.
Between airport waits and long car rides, it helps to have something calm and engaging ready to go.
Netflix Kids Games has games your kids can play without Wi-Fi, perfect for when you're in the air or on the road.
They feature characters like Paw Patrol, Peppa Pig, and Barbie.
And they're educational, too.
Everything's fully unlocked with your Netflix membership, so there are no extra costs.
You can download shows and movies for offline watching, too.
Visit netflixfamily.com slash travel tips. for more ways to make holiday travel easier on everyone.
That's netflixfamily.com slash travel tips.
Happy travels, friends.
Did you know that the deepest diamond ever found started forming over 600 kilometers underground?
What?
That's deeper than the deepest ocean trench.
Friends, and welcome back to Sleep.
Tight Science, a bedtime show that answers your questions about science.
In this episode, we're answering some of the great questions from our listeners all around the world.
We're going to explore six wonderful questions that arrived in our inbox.
Each one helping us learn something fascinating about our world.
We'll discover how mountains grow.
Yes. they're still growing right now even as you listen.
We'll figure out why air is invisible even though it's all around us.
We'll learn why everything in the universe is made of molecules, from the water you drink to the stars in the sky.
We'll journey deep underground to see how diamonds form over billions of years.
We'll meet the tiniest bug on Earth, so small it could fly through the eye of a needle and will travel back in time to meet the strange and wonderful animals that lived before dinosaurs walked the earth.
A quiet thank you to Layla and Lena from Phoenix Arizona for introducing our show and to all our curious friends who send in questions.
You help us learn together.
And thank you to Haley, Colby, Riley, Riley.
Yes, we have two.
Noah and Rita for sending us such thoughtful questions that we featured in this episode.
So get comfortable.
Take a gentle breath in.
And out.
Let's explore the science behind your questions one answer at a time.
The first question comes from Haley, age 6, from Naples, Italy.
Haley asks, How are mountains formed?
Mountains are some of the most spectacular features on Earth, and you're lucky to live near some beautiful ones.
Italy has the Alps to the north and the Apennine Mountains running right down the middle of the country.
The simple answer is mountains form when Earth's crust gets pushed, pulled or squeezed by powerful forces deep below underground.
But let's zoom in a little closer to see how that actually works.
Earth's outer layer, the crust we live on, isn't one solid piece.
It's broken into giant puzzle pieces called tectonic plates.
These plates float on hot, slowly moving rock beneath them.
And they're constantly creeping around, usually a few centimeters per year, about as fast as your fingernails grow.
When these enormous plates bump into each other, push against each other or slide past each other, amazing things happen.
Mountains are one of those amazing things.
There are three main ways mountains can form.
Fold mountains are created when two plates crash together and the crust crumples upward like pushing two ends of a rug toward each other.
The Himalayas formed this way, and they're still growing taller every year.
The Alps near you formed the same way when the African plate pushed into the European plate millions of years ago.
Volcanic mountains are built from erupted material.
When melted rock magma pushes up through cracks in Earth's crust and erupts, it piles up layer after layer, building a mountain over time.
Mount Vesuvius near Naples is a volcanic mountain.
Fault block.
Mountains form when huge chunks of crust break and tilt, pushing some sections up while others drop down.
Mountains grow incredibly slowly, usually just millimeters per year.
But given millions of years, those tiny changes add up to peaks that touch the clouds.
And guess what?
Mountains are still growing right now, even as you drift off to sleep or enjoy some quiet time.
Thank you for the question, Haley.
Our next question comes from Colby, age six. from Utah.
Colby asks, why can't you see air?
Air is all around us.
It fills your room, surrounds your house, wraps around the entire planet.
But you're right.
We can't see it at all.
So what's going on?
The simple answer is air molecules are too tiny and too spread out for our eyes to see.
Air is made mostly of nitrogen and oxygen molecules with tiny amounts of other gases mixed in.
These molecules are incredibly small, so small that millions of them could fit on the period at the end of a sentence.
Your eyes can only see things that are much, much bigger than individual molecules.
But there's another reason air is invisible.
The molecules are spread really far apart from each other.
Imagine a huge empty gymnasium with just a few bouncing balls scattered around.
That's kind of what air is like at the molecular level.
Lots of empty space with molecules zooming around in it.
For us to see something, light has to bounce off it and into our eyes.
But air molecules are so small and so spread out that light just passes right through without bouncing back.
That's what makes air transparent, invisible. but sometimes we can see air.
When there's water vapor in the air that condenses into tiny droplets, we see clouds or fog.
When there's dust or smoke mixed in, we can see it floating.
And on a really hot day you might see heat waves, shimmery ripples where hot air is bending the light.
Even though you can't see air, you can definitely feel it.
The wind blowing through your hair, that's air moving.
When you blow up a balloon, you're filling it with air.
Air has weight.
The atmosphere actually presses down on you with about the same force as a large car sitting on your body.
But you don't notice because your body is used to it.
So air is there working hard all around you even if it stays invisible.
Thank you for the question, Colby.
Question comes from Riley, age six, who lives in Ottawa, Ontario, Canada.
Riley asks, why do molecules make up everything in the world?
You're asking about one of the most fundamental ideas in science, what everything is made of.
Let me start with the simple answer.
Molecules are the building blocks of all matter.
Everything you can touch, see, smell or taste is made of molecules.
Your body, your bed, the air you breathe, the water you drink, even the stars in the sky all made of molecules.
But why molecules?
Why not something else?
Well, Molecules are made of even smaller pieces called atoms.
Atoms are like tiny Lego bricks, the smallest pieces of elements like oxygen hydrogen, carbon and nitrogen.
These atoms bond together in different combinations to form molecules.
And those molecules are what make up everything.
Think of it like this.
If you only had one type of Lego brick you could only build one kind of thing.
But because atoms can connect in millions of different ways, they can create millions of different molecules, and different molecules have completely different properties.
For example, water is made up of two hydrogen atoms bonded to one oxygen atom.
We write that as H2O.
That particular combination creates a liquid you can drink.
But oxygen molecules by themselves, O2, are a gas you breathe.
Same atoms, different arrangements, totally different results.
Your body is made of molecules too.
Protein molecules, fat molecules, and DNA molecules.
The wood of a tree cellulose molecules.
Sugar?
That's a molecule.
Even metals like iron are made of atoms bonded together in special patterns.
The beautiful thing is that there are only about 100 different types of atoms in the universe, but they can combine in countless ways to create everything we see.
It's like having a box of 100 different Lego bricks, but being able to build infinite creations skyscrapers spaceships dinosaurs, whatever you can imagine.
So molecules make up everything, because matter needs to be made of something, and atoms bonding together into molecules is nature's way of building our world, from the tiniest grain of sand to the biggest mountain, from a single snowflake to the entire ocean.
It's all molecules arranged in endlessly creative ways.
Thank you for your question, Riley.
Our next question comes from Riley aged seven. from Bensville, New South Wales, Australia.
Riley asks, how are diamonds made?
The simplest explanation is diamonds are made deep underground from carbon that gets squeezed by enormous pressure and heat for billions of years.
But let's go into more detail and start with what diamonds are made of.
Carbon.
Carbon is the same element you find in pencil lead and charcoal.
But when carbon atoms get arranged in a special way, under extreme conditions they form something completely different.
Sparkling, super hard diamonds.
Diamonds form about 150 to 200 kilometers underground in Earth's mantle.
That's the hot, slowly moving layer of rock beneath the crust.
Down there, conditions are extreme.
The temperature is over 1000 degrees Celsius, hot enough to melt most rocks, and the pressure is incredible.
Imagine thousands of elephants standing on top of each other, all pressing down on a tiny space.
Under these conditions, carbon atoms get squeezed so tightly that they lock together in a super strong crystal structure.
Each carbon atom bonds to four other carbon atoms in a perfect geometric pattern.
This is what makes diamonds the hardest natural material on Earth.
The atoms are holding onto each other incredibly tightly.
This process takes time.
A lot of time.
Most diamonds took between one and three billion years to form.
That's older than the dinosaurs. older than most life on Earth.
So if diamonds form so deep underground, how do we find them?
Volcanic eruptions.
Special volcanic eruptions bring diamonds up from the mantle through narrow pipes called kimberlite pipes.
The diamonds shoot up to the surface incredibly fast, in just a few hours, which is good, because if they came up slowly they'd turn back into graphite.
Did you know that Australia actually has some amazing diamond mines, including the Argyle Mine that produced beautiful pink diamonds?
So the next time you see a diamond, remember that you're looking at carbon that was squeezed deep underground for billions of years and then rocketed to the surface by a volcano.
Thank you, Riley, for your question.
Next question comes from Noah, age seven, from Shropshire, England.
Noah asks, what is the smallest bug in the world?
The smallest bugs in the world are called fairy flies, and they're actually tiny wasps, not flies.
The smallest one ever discovered is called Dicapamorpha acmeptergis.
Quite a mouthful.
And it measures just 0.139 millimeters long.
That's barely visible to the human eye.
Let me help you understand just how small that is.
A period at the end of a sentence is about 05 millimeters across, which means this tiny wasp is smaller than the dot of an eye on a page.
It's about the width of a single human hair.
In fact, It could easily fly through the eye of a sewing needle.
And did you know that fairy flies are smaller than some single-celled organisms like amoebas?
They're smaller than a grain of salt.
If you placed one on your fingertip, you'd probably mistake it for a speck of dust.
But being so tiny comes with challenges.
At that size, air feels thick and sticky, almost like swimming through honey.
So fairy flies have special feathery wings that work more like tiny paddles, helping them swim through the air.
These micro wasps lay their eggs inside the eggs of other insects.
They're so small they can actually crawl inside another bug's egg.
The baby fairy fly grows up eating the egg from the inside.
Scientists discovered these tiny creatures using powerful microscopes.
Some researchers spend years searching through leaf litter and soil samples, looking for these miniature marvels.
So the next time you see a period on a page or a speck of dust floating in a sunbeam, imagine that something even smaller might be flying around out there.
An entire living insect with wings eyes and a tiny beating heart, navigating a world where air feels like water and flowers are like mountains.
Thank you for the question, Noah.
Final question comes from Rita, age 10, from China.
Rita asks, what kind of animals lived before dinosaurs?
Most people think dinosaurs were the first amazing creatures on Earth.
But life had already been evolving for billions of years before the first dinosaur appeared, around 230 million years ago.
And some of those ancient animals were just as weird and wonderful as any dinosaur.
Let's meet some of them.
Trilobites were armored seed creatures that lived from about 540 to 250 million years ago.
They looked a bit like underwater potato bugs. with segmented bodies and lots of legs.
Thousands of different species crawled across ancient ocean floors, and their fossils are found all over the world, including some spectacular ones in China.
Giant insects ruled the skies during the Carboniferous period around 300 million years ago.
Dragonflies with wingspans over 60 centimeters, that's about two feet across, buzz through prehistoric forests.
Millipedes grew as long as cars.
The air had more oxygen back then, which allowed insects to grow much larger than they can today.
Dimetrodon looked like a dinosaur with its huge sail on its back, but it actually lived before dinosaurs and was more closely related to mammals.
This sail-backed predator prowled the land about 280 million years ago.
Anomalocaris was one of the ocean's first big predators, living over 500 million years ago.
It had a circular mouth like a pineapple ring grabbing appendages near its face, and a body that could grow up to a meter long.
Huge for that time.
The rhapsids were mammal-like reptiles that dominated the land before dinosaurs.
Some were ferocious. fierce predators with saber teeth, while others were plant eaters with beaks.
They're important because they're the ancestors of all mammals, including us.
All of these incredible creatures thrived during the Permian period.
But about 252 million years ago, the largest mass extinction in Earth's history wiped out about 90 of all species.
This catastrophe, called the Great Dying, cleared the way for dinosaurs to evolve and take over.
China has some of the world's most amazing fossils from these ancient periods.
Museums across China display creatures that lived hundreds of millions of years ago, proving that Earth's history is full of extraordinary animals we're still discovering.
Thank you for your question, Rita.
Here's a wave to some of our question askers.
Theo, age 9, and Benji, age 5.
Hannah, 5 years old, from San Diego, California.
Ada Rachel Rose Owen.
Seven years old from Malmesbury in southwest England.
Sive from Kerry, England.
Ryan, age eight in Toronto.
Liam.
William. five years old in Cary, North Carolina.
Nask from Canberra, Australia.
Ellis, 11 years old.
Henry in Minnesota.
Margaret, 8 years old, in Toronto, Stella Klisch, 6 years old, in Waco, Texas.
Ethan Turnbull, age 11, from Ottawa Ontario Canada Alyssa, four years old, in Columbia City Indiana, and Grace from Omaha, Nebraska.
Thank you for asking questions that spark our curiosity and keep us learning.
To submit your questions.
Ask your parents to help you.
Write us a note to the email address in our episode notes.
You can also visit our website and send a message that way.
Also, don't forget to leave us a review It helps other people find our show.
Take a slow, deep breath in and let it out gently.
Maybe tonight you'll dream of standing on a mountain that's slowly growing beneath your feet, rising millimeter by millimeter toward the clouds.
You might shrink down small enough to see individual air molecules bouncing and dancing all around you.
Invisible, but always there.
Perhaps you'll become a tiny architect, arranging atoms like Lego bricks into endless combinations, building water molecules, sugar molecules, molecules that shimmer and shine.
You could journey deep underground, waiting patiently as carbon atoms squeeze together over billions of years, slowly transforming into a perfect diamond.
Maybe you'll fly alongside a fairy.
Fly so small you can pass through the eye of a needle, discovering a world where air feels thick and flowers tower like mountains.
Or you might swim through ancient oceans with trilobites watching anomalocaris glide past, long before dinosaurs ever walked the earth.
Your dreams can take you anywhere.
From the highest peaks to the deepest depths.
From the tiniest creatures to the biggest mysteries.
Thank you for spending this time with us.
From Cheryl and Clark.
Good night.
Sleep tight.
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