Latest / Boring Science / How Rockets Escape Earth _ 100 Space Facts for Sleep

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How Rockets Escape Earth _ 100 Space Facts for Sleep · Boring Science

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Speaker 1: Good evening, and welcome back to Boring Science for Sleep. Tonight,
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we're going to explore one of the most powerful and
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fascinating machines humanity has ever created. The rocket. Before we begin,
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settle in somewhere comfortable. Dim the lights if you can,
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relax your breathing, and let your mind slow down for
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a moment. And if you'd like, take a second to
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share something in the comments. Where in the world are
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you watching from tonight? And what time is it there
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right now? Many people enjoy listening to these space stories
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as they fall asleep, and it's always calming to see
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how listeners from all around the world are resting beneath
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the same night sky. Now, let's begin our quiet journey.
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Imagine standing far away from a launch pad in the
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early morning darkness. The air is still. The sky is
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deep blue. just before sunrise, and in the distance stands
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a rocket, tall, silent, almost impossibly large. For hours it
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has waited there, filled with fuel and energy, ready for
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a journey that will carry it beyond Earth's atmosphere. Around it,
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technicians and engineers have prepared every system with extraordinary precision.
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Thousands of tiny details must be perfect, Because launching a
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rocket is one of the most powerful events humanity can create.
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Then the countdown begins.
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Speaker 2: Ten. Nine. Eight.
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Speaker 1: The rocket remains still, but inside it, fuel begins to flow.
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Valves open. Pumps accelerate. Seven. Six. Deep beneath the rocket,
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engines prepare to ignite. Five. Four. Suddenly, the first flames appear.
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Speaker 2: Three. Two.
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Speaker 1: And then, everything changes. With a thunderous roar, engines ignite
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in a burst of fire and light. Columns of flame
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pour downward, brighter than the rising sun. The ground trembles
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as millions of newtons of thrust push against the launch pad.
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For a moment, the rocket seems to hesitate. Then, slowly,
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almost gently, it begins to rise. A machine weighing hundreds
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of tons lifts itself from the Earth. Fire and smoke
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roll across the ground. The rocket climbs higher and higher,
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leaving behind a glowing trail across the sky. Within minutes,
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it will travel faster than a bullet. Soon it will
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reach the edge of space. And eventually, it may circle
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the Earth, or travel toward the Moon, or even journey
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to other planets. all powered by the extraordinary physics of
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rocket engines. Tonight, we'll explore 100 fascinating facts about rocket launches.
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We'll discover how rockets work, why they are able to
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escape Earth's gravity, and how engineers carefully guide them through
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the atmosphere into orbit. Along the way, we'll visit some
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of the most famous launches in history, and we'll imagine
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the future rockets that may one day carry humans far
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beyond Earth But for now, let the sound of distant
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engines fade into the quiet of space. Take a slow
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breath and allow your thoughts to drift gently upward toward
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the stars. Long before rockets thundered into the sky, before
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astronauts floated in orbit, before satellites circled the Earth, the
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idea of traveling into space lived only in human imagination.
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For thousands of years, People looked up at the night
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sky and wondered what lay beyond. The moon drifted slowly
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across the darkness. Planets wandered among the stars. And the
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distant lights of the cosmos shimmered quietly above every civilization
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that had ever existed. But no matter how much people
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dreamed of reaching those distant worlds, there was one problem
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that seemed impossible to overcome. Gravity. The Earth holds everything
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close to its surface. Every stone that is thrown eventually
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falls back down. Every bird that rises into the air
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must return to the ground. Even the tallest mountains barely
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reach the thin edges of the atmosphere. For most of
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human history, the idea of leaving the Earth entirely seemed
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as impossible as touching the stars themselves. Yet even in
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ancient times, people experimented with ways of creating thrust. One
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of the earliest ancestors of the modern rocket appeared in
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China more than a thousand years ago. During the early
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development of gunpowder, inventors discovered that when certain mixtures of
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chemicals burned rapidly, they produced powerful jets of gas. At first,
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this discovery was used mainly for fireworks. Small tubes filled
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with gunpowder could shoot sparks into the sky, exploding in
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bright colours. But eventually someone realised that if the tube
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was left open on one end, the escaping gas would
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push the tube in the opposite direction. In other words,
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the tube would move. These early devices were simple and unpredictable,
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but they were the first true rockets. They were often
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attached to arrows and used in warfare. When ignited, they
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would launch themselves across the battlefield, trailing smoke and flame.
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Compared to modern rockets, they were crude and unreliable. But
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they demonstrated something important. a burning fuel could create thrust,
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and that thrust could move an object through the air.
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Centuries passed before anyone began to understand the deeper physics
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behind rockets. The key idea came from a simple principle
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of motion. Whenever something pushes in one direction, an equal
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force pushes back in the opposite direction. This principle would
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later be described formally by Isaac Newton as his famous
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third law of motion. But even before Newton wrote down
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the equation, people could observe this effect in everyday life.
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A balloon filled with air will shoot across a room
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when released. The escaping air pushes backward. The balloon moves forward.
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Rockets work in a similar way. Instead of air escaping
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from a balloon, extremely hot gases shoot out of a
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rocket engine. Those gases rush downward at tremendous speed, and
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the rocket is pushed upward. Still, for centuries, rockets remained
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mostly small devices used for fireworks and simple weapons. No
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one seriously imagined using them to travel beyond the Earth.
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The idea seemed far too unrealistic, until one quiet school
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teacher in Russia began thinking about it. His name was
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Konstantin Tsiolkovsky, and he would become one of the most
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important pioneers in the history of spaceflight. Tsiolkovsky lived in
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the late 19th and early 20th centuries. He spent much
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of his life working as a mathematics teacher in a
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small town. But in his spare time, he thought deeply
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about the possibility of space travel. Unlike many people of
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his era, Tsiolkovsky believed that reaching space might actually be possible.
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He understood that rockets did not need air in order
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to work. This was a crucial insight. Many people once
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believed that rockets could not function in the vacuum of
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space because there would be nothing for the rocket to
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push against. But Tsiolkovsky realised that rockets push against their
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own exhaust gases. As long as fuel burns and gases
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shoot out of the engine, the rocket will continue to accelerate,
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even in the vacuum of space. In 1903, Tsiolkovsky published
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a remarkable scientific paper describing the mathematics of rocket propulsion.
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In this paper, he introduced what is now known as
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the rocket equation. This equation explains how a rocket's speed
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depends on the velocity of its exhaust and the ratio
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between its fuel mass and its empty mass. Although the
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equation may appear complicated, its meaning is simple. To reach
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high speeds, rockets must carry large amounts of fuel. But
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carrying fuel also adds weight. And the heavier the rocket becomes,
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the harder it is to accelerate. Tsiolkovsky realized that solving
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this problem would require rockets built in multiple stages. The
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idea of multi-stage rockets was revolutionary. Instead of a single
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rocket carrying all its fuel from start to finish, a
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rocket could be built in sections. Once the fuel in
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one stage was used up, that stage could be discarded.
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The remaining rocket would then be lighter and able to
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accelerate more efficiently. This concept would later become essential for
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launching spacecraft into orbit. Nearly every modern rocket still follows
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this basic principle. Tsiolkovsky also imagined technologies that would not
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become reality until many decades later. He wrote about space
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stations orbiting the Earth, about spacecraft travelling between planets, and
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even about human colonies living in space. At the time,
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these ideas sounded like science fiction. After all, no rocket
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had ever reached space. No human had ever left the Earth.
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Yet Tsiolkovsky believed that humanity's future lay beyond our planet.
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One of his most famous lines captured that vision perfectly.
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The Earth is the cradle of humanity, but mankind cannot
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stay in the cradle forever. Although Tsiolkovsky himself never built
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a rocket... His ideas inspired generations of engineers and scientists.
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His equations provided the foundation for modern rocket science. Later
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pioneers such as Robert Goddard in the United States and
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Herman Oberth in Europe would begin turning those theories into
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real machines. Slowly, the dream of leaving Earth began moving
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from imagination to engineering. From sketches and equations to engines
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and fuel tanks, from quiet thoughts written on paper to
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roaring rockets rising into the sky. And so the dream
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that once seemed impossible began to take shape. Humans had
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always looked up at the stars with wonder. Now, for
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the first time, they were beginning to understand how a
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machine might carry them there. The journey to space had
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not yet begun, but the idea of it, the dream
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of leaving Earth, had already taken flight. And in the
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next part of our journey, We will explore the physics
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that makes rockets possible, because the secret behind every rocket
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launch lies in a simple but powerful law of motion.
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A law that explains how fire and fuel can lift
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hundreds of tons into the sky and send them racing
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towards space. Now that we have explored the early dream
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of leaving Earth, we arrive at one of the most
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fascinating questions in all of spaceflight. How does a rocket
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actually work? At first glance, rockets seem almost magical. A
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massive machine, often weighing hundreds of tons, rises slowly into
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the sky, surrounded by roaring flames and clouds of smoke.
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Within minutes, it accelerates faster than the speed of sound,
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eventually traveling fast enough to remain in orbit around the Earth.
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But behind this dramatic spectacle lies a simple physical principle.
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A principle that was first described more than 300 years
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ago by Isaac Newton. Newton's third law of motion. This
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law states something very straightforward. For every action, there is
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an equal and opposite reaction. It may sound abstract at first,
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but this rule appears everywhere in everyday life. If you
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push against a wall, the wall pushes back against you.
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If you jump off a small boat into the water,
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the boat moves backward. And if air rushes out of
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a balloon, the balloon shoots forward in the opposite direction.
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Rockets operate according to exactly the same principle. Inside a
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rocket engine, fuel and oxidizer are mixed together and burned
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in an extremely powerful chemical reaction. This reaction produces enormous
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amounts of hot gas. The gas expands rapidly as it
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heats up, creating pressure inside the engine's combustion chamber. But
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the gas cannot escape in every direction. Instead, it is
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forced through a narrow opening at the bottom of the
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engine called the nozzle. As the gas rushes out of
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the nozzle at tremendous speed, it shoots downward. And according
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to Newton's third law, if the exhaust gas is pushed downward,
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the rocket itself must be pushed upward. This upward push
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is known as thrust. Thrust is the force that lifts
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the rocket from the launch pad and drives it towards space.
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The amount of thrust produced by a rocket depends on
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two main factors. First, how much mass is expelled from
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the engine. Second, how fast that mass is expelled. The
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more gas that flows through the engine and the faster
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it leaves the nozzle, the greater the thrust. Rocket engines
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therefore operate under extreme conditions. Inside the combustion chamber, temperatures
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can reach thousands of degrees. The pressure becomes immense. Fuel
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is burned at astonishing rates, sometimes hundreds of kilograms every second.
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All of this energy is converted into a powerful stream
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of exhaust gas shooting out of the rocket. And that
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stream of gas is what lifts the rocket skyward. One
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of the most interesting features of rockets is that they
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carry both fuel and oxidizer. This might seem unusual at first.
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Most engines on Earth, such as car engines or jet engines,
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burn fuel using oxygen from the surrounding air. But rockets
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cannot rely on the atmosphere. Once a rocket reaches space,
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there is no air available. Without oxygen, ordinary combustion would stop.
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So rockets bring their own oxygen with them, in the
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form of an oxidizer. Inside the rocket's tanks, the fuel
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and oxidizer are stored separately. They are pumped into the
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engine where they mix and ignite. This allows rockets to
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function not only within the atmosphere but also in the
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vacuum of space. It is one of the key differences
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between rockets and other types of engines. Many different types
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of rocket fuel have been used throughout the history of spaceflight.
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Some rockets use liquid fuels which are stored in tanks
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and pumped into the engine. For example, one common combination
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is liquid hydrogen as fuel. and liquid oxygen as oxidizer.
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This mixture burns extremely efficiently and produces very high exhaust speeds.
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The exhaust from hydrogen engines is mostly water vapor. Other
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rockets use kerosene-based fuels, similar to refined rocket-grade kerosene known
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as RP-1. When combined with liquid oxygen, kerosene produces powerful
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thrust and is easier to store than hydrogen. This type
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of fuel has been used in many famous rockets, including
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the Saturn V that carried astronauts to the moon. There
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are also rockets that use solid fuel. Instead of liquids
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stored in tanks, solid rocket motors contain a mixture of
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fuel and oxidizer packed into a solid block. When ignited,
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the fuel burns steadily until it is completely consumed. Solid
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rockets are simpler than liquid engines because they have fewer
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moving parts. However, once they are ignited, they cannot easily
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be turned off. For this reason, solid rocket boosters are
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often used during the early stages of launch when maximum
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thrust is needed. The Space Shuttle, for example, used two
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enormous solid rocket boosters to help lift the spacecraft from
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the launch pad. Another important part of rocket design is
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the shape of the engine's nozzle. The nozzle is carefully
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engineered to accelerate exhaust gases to extremely high speeds. Inside
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the combustion chamber, gases begin under very high pressure. As
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they flow through the narrow throat of the nozzle and
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expand outward, their speed increases dramatically. By the time the
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gases exit the nozzle, they may be traveling several kilometers
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per second. This incredible speed is what gives rockets the
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ability to produce such powerful thrust. Despite their enormous power,
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rockets must overcome one major challenge. They're extremely heavy at liftoff.
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Most of a rocket's weight is not the spacecraft itself.
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It is the fuel. In fact, in many rockets, more
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than 90% of the total mass at launch is fuel
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and oxidizer. As the rocket burns fuel during ascent, it
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gradually becomes lighter. This allows it to accelerate more easily.
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The physics of this process was first described by Tsiolkovsky's
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rocket equation, which we discussed earlier. The equation shows that
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achieving high speeds requires burning large amounts of propellant. That
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is why rockets are often so large and carry enormous
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fuel tanks. When you watch a rocket launch, the flames
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and smoke may appear chaotic, but in reality the process
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is incredibly precise. Thousands of sensors monitor temperature, pressure, fuel flow,
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and engine performance. Computers constantly adjust the engine's operation to
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maintain stable thrust. Guidance systems ensure the rocket follows its
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planned trajectory. Every second of the launch must be carefully controlled,
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because even a small error could lead to failure. Yet
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when everything works perfectly, the result is extraordinary. A machine
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built on Earth rises through the sky, powered only by fire, fuel,
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and the simple physics of Newton's laws. And as the
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rocket climbs higher and higher, another phase of the journey begins.
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Because reaching space is not only about producing thrust, it
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is also about surviving the intense forces that occur during
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ascent through the atmosphere. The air becomes thinner, the rocket
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accelerates faster, and the stresses on the vehicle grow stronger.
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In the next part of our journey, we will explore
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the carefully orchestrated process that leads up to every launch.
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The quiet preparations, the final checks, and the dramatic countdown
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that begins just moments before the engines ignite. Long before
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a rocket rises into the sky, the most delicate part
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of the journey begins. has already begun. The countdown. To
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an outside observer, a rocket launch might appear to happen suddenly.
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One moment the rocket stands quietly on the launch pad.
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The next moment flames burst from its engines and it
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climbs into the sky. But in reality... A launch is
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the result of many hours, sometimes even days, of careful preparation.
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Every system must be checked. Every sensor must be monitored.
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Every valve and computer must operate perfectly. Because once the
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engines ignite, there is very little time to correct mistakes.
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The process begins many hours before liftoff. Engineers and technicians
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gather in control rooms filled with screens and instruments. Some
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sit inside the launch control centre near the rocket itself.
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Others work from mission control facilities hundreds or even thousands
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of kilometres away. Together, they monitor thousands of parameters. Fuel levels, temperatures,
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pressure inside the tanks, electrical systems, communication links, navigation systems.
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Each of these elements must be working properly before the
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launch can continue. Meanwhile, the rocket itself remains standing quietly
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on the launch pad. At this stage, it is often
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connected to large structures known as launch towers. These towers
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provide access to the rocket for technicians and supply systems
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for fuel, power and data. From a distance, the rocket
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may appear still and silent. But inside it, preparations are
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already underway. Valves are tested. Pumps are checked. Sensors measure
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the conditions within the vehicle. The rocket is slowly coming
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to life. One of the most important steps during the
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countdown is fueling. Rocket propellants are often extremely cold liquids.
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For example, liquid hydrogen must be stored at temperatures near
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minus 250 degrees Celsius. Liquid oxygen is also cryogenic, meaning
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it must remain extremely cold to stay in liquid form.
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Fueling a rocket with these propellants requires careful timing. The
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tanks are gradually filled while engineers monitor temperature and pressure.
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Pipes and valves must remain stable despite the extreme cold.
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Even small leaks or temperature changes can cause serious problems.
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For this reason, fueling operations are among the most critical
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phases of the countdown. As the launch window approaches, the
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pace of activity begins to increase. More systems come online.
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Computers begin running automated checks. Engineers carefully review the data
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flowing across their screens. If anything appears unusual, the countdown
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can be paused. This is known as a hold. During
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a hold, the clock stops while teams investigate the issue.
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Sometimes the problem can be solved quickly. Other times the
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launch must be postponed to another day. Safety always comes first.
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Inside mission control, the atmosphere is often surprisingly calm. Despite
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the complexity of the operation, the room remains quiet. Controllers
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speak clearly and precisely over communication loops. Each specialist is
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responsible for a specific system. One person monitors propulsion. Another
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watches electrical systems. Another tracks navigation and guidance. One by one,
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they report their status. Propulsion is go. Guidance is go.
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Flight computers are go. These confirmations gradually build toward the
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final decision. Whether the rocket is ready to fly. As
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the countdown reaches its final minutes, more processes become automated.
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The rocket's onboard computers begin controlling many of the systems directly.
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Fuel tanks are pressurized. Engine chill-down procedures begin, allowing extremely
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cold propellants to flow through the engines before ignition. This
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prepares the hardware for the sudden rush of fuel that
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will soon follow. At this stage, even small details are
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carefully managed. Wind conditions are measured. Weather radar scans the
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sky for lightning or storms. Range safety officers ensure the
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launch corridor is clear. Every factor must align before the
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rocket can leave the ground. Then the final countdown begins.
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10 minutes. 5 minutes. 1 minute. Inside mission control, voices
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remain steady as each milestone passes. 30 seconds. At this moment,
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the rocket is almost entirely in control of itself. Its
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computers monitor every system. If something goes wrong, the rocket
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can automatically abort the launch. But if everything remains within
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safe limits, the sequence continues. Ten seconds. The rocket's engines
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prepare to ignite. Valves open. Fuel begins rushing into the
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combustion chambers. Nine.
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Speaker 2: Eight.
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Speaker 1: The engines begin their start-up sequence. Seven. Six. Inside the rocket...
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Turbopumps spin faster and faster, forcing fuel and oxidizer toward
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the engines. Five. Four. Flames begin to appear beneath the rocket. Three.
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Speaker 2: Two.
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Speaker 1: The engines reach full power. And finally.
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Speaker 2: One.
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Speaker 1: At that moment, the enormous clamps holding the rocket to
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the launch pad release. For a brief instant, the rocket
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seems to hover. Then, slowly, almost gently, it begins to rise.
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Flames spread across the launch pad. Clouds of steam and
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smoke roll outward. The rocket climbs into the sky, carrying
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its cargo towards space. The countdown is over. The journey
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has begun. But the rocket's challenge is only just beginning.
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Within seconds, it will accelerate to incredible speeds. The atmosphere
26:26
will push against it with enormous force, and the vehicle
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must remain stable as it climbs toward orbit. In the
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next part of our journey, we will explore the moment
26:36
of liftoff itself, the thunderous power of rocket engines, and
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the immense energy required to lift a spacecraft away from
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the Earth. For hours, the rocket has stood quietly on
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the launch pad, fuel tanks filled, systems checked. Computer's ready. Then,
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in a matter of seconds, everything changes. The engines ignite.
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A burst of light appears beneath the rocket, growing brighter
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and brighter as the fuel begins to burn. Flames spread
27:11
outward across the launch platform, glowing orange and white against
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the early morning sky. The quiet stillness of the launch
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pad is replaced by one of the most powerful forces
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humans have ever created. the moment of liftoff has arrived.
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Rocket engines produce extraordinary amounts of energy. Inside each engine,
27:32
fuel and oxidizer mix together and burn at temperatures hotter
27:36
than molten lava. The resulting gases expand rapidly, rushing through
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the engine's nozzle and blasting downward at incredible speed. The
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force created by this exhaust is enormous. For example, the
27:51
Saturn V rocket which carried astronauts to the moon produced
27:54
about 35 million newtons of thrust at liftoff. That is
27:59
roughly equivalent to the combined power of dozens of large
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jet aircraft engines operating at once. It is the kind
28:07
of energy required to lift a machine weighing thousands of
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tons into the sky. But before the rocket begins to move,
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something interesting happens. The engines ignite first, while the rocket
28:19
remains firmly held in place by large clamps on the
28:22
launch pad. For a few seconds, the engines run at
28:26
full power. Sensors measure the thrust and check that each
28:30
engine is operating correctly. Only when everything is confirmed to
28:34
be functioning properly do the clamps release. This short moment
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ensures that the rocket will not attempt a launch if
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any engine is underperforming. Once the clamps release, gravity and
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thrust compete. At first, the rocket rises slowly. This surprises
28:52
many people who expect rockets to leap instantly into the sky,
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but the rocket's thrust is only slightly greater than its
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weight at liftoff, so the vehicle climbs gently at first,
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almost as if it is carefully lifting itself away from
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the Earth. Beneath the rocket, the flames are astonishing. The
29:11
exhaust plume can reach temperatures of several thousand degrees, The
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gases move so quickly that they form powerful shock waves
29:20
as they collide with the ground and surrounding air. Large
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clouds of steam often billow across the launch pad. This
29:28
steam is sometimes created intentionally by water systems that flood
29:32
the launch platform just before ignition. The water helps cool
29:36
the surface and reduce the intense acoustic energy produced by
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the engine. Without this system the sound waves could potentially
29:43
damage the rocket itself. The sound of a rocket launch
29:47
is unlike anything most people have ever heard. At a
29:51
safe viewing distance spectators often see the rocket begin rising silently. Then,
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several seconds later, the sound finally arrives. A deep, rolling
30:03
thunder that seems to shake the ground. The noise can
30:07
exceed 180 decibels near the launch pad, louder than almost
30:11
any other human-made sound. It is not just a single roar. Instead,
30:17
it is a complex mixture of vibrations, shock waves and
30:21
rumbling energy. The air itself seems to tremble. Even buildings
30:26
several kilometers away may feel the vibrations Inside the rocket, astronauts,
30:32
if there are any aboard, experience the launch in a
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very different way. Instead of hearing the external roar clearly,
30:39
they feel powerful vibrations through the spacecraft. The engines generate
30:44
enormous mechanical forces that travel through the structure of the rocket.
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Seats and harnesses hold the astronauts firmly in place. As
30:53
the rocket climbs, they feel the pressure of acceleration pushing
30:57
them into their seats. At liftoff, the force may be
31:01
only slightly greater than normal gravity. But as the rocket
31:05
burns fuel and becomes lighter, the acceleration gradually increases. Soon
31:11
the astronauts may experience two, three or even four times
31:14
the force of gravity. Despite the intense forces, the ride
31:19
is carefully controlled. Modern rockets are designed to minimize dangerous
31:24
vibrations that could damage the spacecraft or injure the crew.
31:28
Engineers study the physics of these vibrations in great detail
31:33
to ensure a safe ascent. Another fascinating aspect of liftoff
31:38
is the enormous amount of fuel consumed during the first
31:41
minutes of flight. Rocket engines burn propellant at astonishing rates.
31:46
For example, the Saturn V consumed roughly 13 tonnes of
31:51
fuel every second during its first stage burn. Imagine an
31:55
entire truckload of fuel disappearing every second. Yet this massive
32:00
consumption is necessary. Escaping Earth's gravity requires enormous energy, and
32:06
that energy must come from the chemical reactions occurring inside
32:10
the rocket's engines. As the rocket rises higher, it begins
32:14
to accelerate more quickly. The engines continue firing at full power.
32:20
The vehicle climbs through the lower atmosphere, leaving behind a
32:23
long trail of exhaust. From the ground, this trail often
32:28
appears as a brilliant white plume stretching across the sky.
32:32
Sunlight reflecting from the exhaust can make the rocket visible
32:36
from hundreds of kilometers away. For observers on the ground,
32:41
the sight can be breathtaking. A glowing pillar of fire
32:45
carrying a spacecraft toward the edge of space. Yet even
32:50
during this dramatic ascent, the rocket must follow a carefully
32:53
planned trajectory. It does not travel straight upward for very long. Instead,
33:00
it gradually begins to tilt sideways. This maneuver is called
33:04
the Gravity Turn. The goal is not simply to rise
33:08
high above the Earth. The goal is to build horizontal speed.
33:12
Because reaching orbit requires moving sideways around the planet at
33:16
incredible velocity. The rocket must therefore begin turning toward its
33:21
orbital path soon after liftoff. Within just a few minutes,
33:25
the rocket will already be traveling faster than the speed
33:28
of sound. Soon after that, it will approach several kilometers
33:33
per second. The violent energy of liftoff gradually gives way
33:37
to the smooth acceleration of high altitude flight. But during
33:41
those first moments on the launch pad, when engines ignite
33:44
and flames erupt beneath the rocket, humanity witnesses one of
33:48
its most dramatic technological achievements. A machine powerful enough to
33:53
rise from the Earth, carried upward by fire, fuel and physics.
33:59
And as the rocket climbs higher through the sky, it
34:01
faces its next great challenge. The atmosphere itself. Air rushing
34:07
past the rocket creates enormous aerodynamic forces. At a certain
34:12
point during ascent, those forces will reach their maximum. a
34:16
moment known as Max Q. In the next part of
34:20
our journey, we will explore how rockets break through the
34:23
atmosphere and survive the intense pressure of their climb towards space.
34:29
After the thunderous moment of liftoff, the rocket continues its
34:33
journey upward through the sky. Below it, the launch pad
34:37
quickly disappears beneath clouds of smoke and steam. The vehicle
34:41
accelerates rapidly, climbing higher and higher, as its engines burn
34:46
through massive quantities of fuel. But even though the rocket
34:50
is heading toward the vacuum of space, its first challenge
34:54
is not empty space. It is the atmosphere. The Earth's
34:58
atmosphere forms a vast ocean of air surrounding the planet.
35:02
From the ground up to the edge of space, the
35:05
rocket must travel through layers of gas that push against
35:08
it as it accelerates. At first, the air is thick
35:12
and heavy. But as the rocket climbs, The atmosphere gradually
35:16
becomes thinner. The rocket must be carefully designed to survive
35:20
this transition. The lowest layer of the atmosphere is called
35:24
the troposphere. This is the region where weather occurs. Clouds
35:29
form here. Storms develop. Airplanes fly within this layer. The
35:35
troposphere extends roughly 10 to 15 kilometers above the Earth's surface.
35:40
When a rocket launches, It passes through this region within
35:43
the first minute or two of flight. During this phase,
35:47
the rocket experiences strong aerodynamic forces. Air rushes past the
35:53
vehicle at increasing speed. The faster the rocket moves, the
35:57
harder the air pushes against it. This resistance is known
36:01
as aerodynamic drag. As the rocket accelerates, something interesting happens.
36:08
Even though the atmosphere becomes thinner as altitude increases, the
36:11
rocket's speed is increasing at the same time. For a
36:15
short period during ascent, these two effects combine in a
36:19
very important way. The rocket is moving extremely fast while
36:23
still passing through relatively dense air. This creates the moment
36:27
of greatest aerodynamic stress during the entire launch. This moment
36:32
is known as Max Q. The name comes from the
36:36
letter Q. which engineers use to represent dynamic pressure the
36:40
force created by air pushing against a moving object. At
36:44
max Q, the pressure on the rocket's structure reaches its
36:48
maximum value. During this critical moment, the rocket experiences enormous forces.
36:55
The air rushing past the vehicle presses against its surface.
36:59
The rocket's body bends slightly under the stress. The engines
37:03
continue pushing upward while aerodynamic forces push against the sides
37:07
of the vehicle. Engineers must carefully design rockets to withstand
37:12
these stresses without breaking apart. Even small structural weaknesses could
37:17
become dangerous during Max-Q. For this reason, rocket designers spend
37:22
years studying how aerodynamic forces affect every part of the vehicle. Interestingly,
37:29
rocket engines are sometimes throttled down during Max-Q, This means
37:33
the engines temporarily reduce their power. By slightly lowering the thrust,
37:39
the rocket's acceleration decreases for a short time. This prevents
37:43
the aerodynamic pressure from becoming too extreme. Once the rocket
37:47
climbs higher and the air becomes thinner, the engines can
37:51
safely return to full power. Many astronauts describe this moment
37:56
during launch. They feel the engines briefly reduce thrust, then
38:00
surge again as the rocket passes through Max Q. It
38:04
is one of the many, carefully controlled phases of ascent.
38:08
The shape of the rocket itself also plays a crucial
38:11
role in surviving atmospheric flight. Rocket bodies are designed to
38:15
be aerodynamic. This means they are shaped in a way
38:19
that reduces drag and allows air to flow smoothly around
38:23
the vehicle. The long cylindrical body and pointed nose cone
38:27
help minimize resistance as the rocket slices through the atmosphere.
38:32
Without this streamlined shape, the rocket would experience far greater
38:36
drag and heating during ascent. The design of the nose
38:39
cone is especially important. As the rocket moves faster and faster,
38:45
air compresses in front of the vehicle. This can create
38:48
intense heating. The smooth, tapered shape helps reduce this effect.
38:54
Attached to the top of many rockets is a structure
38:57
known as the payload fairing. The fairing protects the spacecraft
39:01
or satellite during the early stages of flight. Inside it,
39:06
delicate equipment must remain safe from aerodynamic forces and heating.
39:10
The fairing acts like a protective shell, shielding the payload
39:15
while the rocket passes through the thickest parts of the atmosphere.
39:19
But once the rocket climbs high enough, the atmosphere becomes
39:23
extremely thin At that point, the fairing is no longer needed.
39:28
Carrying unnecessary weight would only slow the rocket down. So
39:32
the fairing separates from the vehicle and falls away. From
39:36
the ground, this event is rarely visible. But high above
39:40
the Earth, the rocket becomes lighter and more efficient as
39:44
it continues towards space. By this stage of the flight,
39:48
the rocket is already traveling incredibly fast. Within just a
39:53
few minutes after liftoff, it may be moving several times
39:56
the speed of sound. The air around it becomes thinner
40:00
and thinner. Eventually, the rocket reaches the upper layers of
40:05
the atmosphere. Here, the sky grows darker. The blue of
40:09
the daytime sky fades into deep black. Stars begin to
40:14
appear even while the sun shines brightly below, This transition
40:19
marks the rocket's gradual arrival at the edge of space.
40:22
Above the troposphere lies the stratosphere, where the ozone layer
40:27
absorbs much of the Sun's ultraviolet radiation. Higher still are
40:31
the mesosphere and thermosphere, where the atmosphere becomes so thin
40:36
that individual molecules are separated by vast distances. By the
40:40
time the rocket reaches these heights, aerodynamic forces are greatly reduced.
40:46
The vehicle is now moving through air that is barely
40:49
there at all. The roaring struggle against the atmosphere slowly fades.
40:54
The rocket's journey becomes smoother and quieter. But the climb
40:58
is not finished yet. Even though the rocket has nearly
41:01
escaped the atmosphere, it still needs one more essential element
41:05
to complete its journey.
41:07
Speaker 2: Speed.
41:09
Speaker 1: To remain in orbit around the Earth, the spacecraft must
41:12
travel sideways at incredible velocity. Reaching this speed requires another
41:17
clever feature of rocket design, the use of multiple stages.
41:22
In the next part of our journey, we will explore
41:25
how rockets shed empty fuel tanks and continue accelerating higher
41:29
into space, a process that allows them to overcome gravity
41:34
and carry their payloads into orbit around our planet. As
41:39
the rocket climbs higher into the sky, something remarkable begins
41:43
to happen. parts of the rocket start to fall away.
41:47
To someone watching from the ground, this may sound alarming,
41:52
but in the world of rocket engineering, it is not
41:55
a failure at all. It is a carefully planned event.
41:59
One of the most important ideas that makes modern spaceflight possible,
42:04
the concept of multistage rockets. Earlier, we learned that rockets
42:09
must carry enormous amounts of fuel. In fact, Most of
42:13
the mass of a rocket at liftoff is not the
42:15
spacecraft itself. It is the propellant needed to escape Earth's gravity.
42:21
But this creates a difficult problem. Once the fuel in
42:25
a tank has been burned, the empty tank becomes useless weight.
42:29
If the rocket continues carrying that empty structure, it must
42:33
spend extra energy accelerating something that no longer serves a purpose. Engineers, therefore,
42:39
came up with a clever solution. Instead of building one
42:43
single rocket, they build several rockets stacked on top of
42:46
each other. Each section is called a stage. A multi-stage
42:51
rocket works like a relay race. The first stage does
42:55
the hardest work. It lifts the entire vehicle from the
42:59
launch pad and pushes it through the thick lower atmosphere.
43:03
This stage carries powerful engines and large fuel tanks. But
43:08
once its fuel is exhausted, The first stage has done
43:11
its job. Instead of continuing to carry the empty tanks,
43:16
the rocket releases that stage. Large mechanical clamps separate the structure.
43:22
Small explosive bolts or pneumatic systems trigger the release, and
43:27
the empty stage falls away from the rest of the rocket. Suddenly,
43:31
the vehicle becomes lighter. The remaining stages can now accelerate
43:36
more efficiently. The moment of stage separation is one of
43:40
the most dramatic parts of a launch. High above the earth,
43:43
the empty booster detaches and drifts away. Sometimes small separation
43:48
motors push the stage slightly backward to ensure a safe distance. Meanwhile,
43:54
the engines of the next stage ignite. For a brief moment,
43:58
there is a pause between the shutdown of one stage
44:01
and the ignition of the next. Then the new engines
44:04
burst to life. continuing the climb towards space. The rocket
44:09
moves faster and faster as each stage contributes its portion
44:13
of energy. The importance of staging was first described mathematically
44:18
by Konstantin Tsiolkovsky. His rocket equation revealed that achieving high
44:23
speeds requires extremely high fuel mass, but if a rocket
44:27
carries all its empty tanks for the entire flight, it
44:30
becomes inefficient. By discarding those empty sections along the way,
44:35
the rocket effectively sheds weight. This makes it easier to
44:39
accelerate the remaining mass. The result is a far more
44:43
efficient vehicle. Without staging, reaching orbit would be vastly more difficult.
44:49
In many cases, it might even be impossible with chemical rockets.
44:54
Most rockets today use two or three stages. The first
44:58
stage provides the enormous thrust needed to escape the launch
45:02
pad and climb through the lower atmosphere. The second stage
45:06
continues accelerating the rocket once it reaches higher altitudes where
45:10
the air is thinner. In some missions, a third stage
45:14
may ignite later to push the spacecraft even faster. This
45:18
final stage might send a satellite into high orbit or
45:21
propel a spacecraft toward the moon or other planets. Each
45:25
stage is optimized for its specific task. The engines used
45:30
in different stages may also vary. First stage engines must
45:34
produce enormous thrust to lift the rocket against gravity. They
45:38
often burn fuel very quickly and generate massive exhaust plumes.
45:44
Upper stage engines, on the other hand, operate in the
45:47
vacuum of space. In this environment, engines can use larger
45:52
nozzles designed to expand exhaust gases more efficiently. These engines
45:56
may produce less thrust than first stage engines. but they
46:00
are optimized for efficiency and long duration burns. Together, the
46:05
stages work in harmony, gradually increasing the rocket's speed. For
46:10
many decades, the stages of rockets simply fell back to
46:14
Earth after separation. The first stage would drop into the
46:18
ocean or burn up in the atmosphere. This was considered normal.
46:22
Rocket launches were expensive, and most of the hardware was
46:26
used only once. But in recent years, a new development
46:30
has changed the way some rockets operate. Some boosters are
46:34
now designed to return to Earth and land safely after separation.
46:38
Companies like SpaceX have developed rockets whose first stages perform
46:43
controlled descents and land vertically on landing pads or floating
46:47
platforms at sea. Watching a massive rocket booster descend slowly
46:52
and land upright has become one of the most extraordinary
46:55
sights in modern spaceflight. It represents a major step toward
47:00
reusable rockets. Even with reusable boosters, the principle of staging
47:06
remains essential. Each stage plays a specific role in overcoming
47:11
gravity and building speed. Without staging, rockets would need to
47:15
carry enormous amounts of extra fuel. The vehicle would become
47:19
too heavy to launch efficiently. By dividing the journey into stages,
47:24
engineers allow each part of the rocket to contribute its
47:28
energy at the right moment. Once that task is complete,
47:32
the empty hardware can be discarded. The rocket becomes lighter, faster,
47:38
more efficient. By the time the final stage ignites, the
47:42
rocket may already be hundreds of kilometers above the Earth.
47:46
The atmosphere has nearly vanished. The sky is completely black. Below,
47:53
curvature of the planet becomes visible. At this point, the
47:57
rocket is no longer simply climbing upward. Its mission has changed.
48:02
It must now achieve a very specific speed. A speed
48:06
that allows it to remain in orbit around the Earth.
48:09
And reaching that speed requires one final step in our
48:13
journey through rocket science. Understanding how spacecraft achieve the incredible
48:18
velocities needed to circle the planet without falling back to
48:22
the ground. By the time a rocket has burned through
48:26
its early stages and climbed beyond most of the atmosphere,
48:29
it has already travelled hundreds of kilometres above the Earth.
48:33
From this altitude, the planet begins to look very different.
48:37
The sky is no longer blue. Instead, it fades into
48:42
deep black. The thin glow of the atmosphere forms a
48:45
faint blue curve along the edge of the Earth. Clouds
48:49
drift slowly across the continents far below, and above the rocket,
48:54
The stars shine clearly even in daylight. At this point,
48:58
the rocket is approaching the edge of space. But surprisingly,
49:03
reaching space is not the main challenge. The real challenge
49:07
is staying there. Many people imagine that spacecraft reach orbit
49:11
simply by flying upward high enough. But this is not
49:14
quite how it works. In fact, altitude alone is not
49:19
enough to remain insane. space. Even if a rocket were
49:22
able to fly straight up to a height of several
49:25
hundred kilometers, gravity would still be pulling it back toward Earth.
49:29
Without sufficient speed, the spacecraft would eventually fall back down.
49:35
To remain in orbit, a spacecraft must achieve an incredible
49:39
sideways velocity. Instead of simply climbing upward, it must travel
49:44
fast enough to continuously fall around the Earth without ever
49:47
hitting the ground. This delicate balance between speed and gravity
49:52
is what creates orbit. For spacecraft circling the Earth in
49:56
low Earth orbit, this required speed is roughly 28,000 km
49:59
per hour. That is about 7.8 km per second. At
50:06
this velocity, the spacecraft moves so quickly that as it
50:10
falls toward the Earth under gravity, the surface of the
50:13
planet curves away beneath it. The result is a continuous
50:17
state of falling that never ends. The spacecraft keeps missing
50:21
the Earth as it moves forward, and so it circles
50:24
the planet again and again. This is what we call orbit.
50:29
The idea can be imagined with a simple thought experiment.
50:33
Suppose you stood on a very tall mountain and threw
50:36
a ball forward. At first, the ball would travel a
50:40
short distance before falling to the ground. If you threw
50:43
it faster, it would travel farther before landing. Now imagine
50:48
throwing it faster and faster. Eventually, if the ball moved
50:53
fast enough, the earth would curve away beneath it at
50:56
the same rate that gravity pulled it downward. The ball
51:00
would never touch the ground. Instead, it would continue circling
51:05
the planet. This is essentially how orbit works. Only rockets
51:10
must accelerate spacecraft to extremely high speeds to achieve it.
51:14
Because orbit depends on sideways velocity, rockets do not travel
51:18
straight upward for very long. Shortly after liftoff, the rocket
51:23
begins a maneuver known as the gravity turn. Instead of
51:26
pointing straight up, the rocket slowly tilts sideways. At first,
51:31
the angle is very small, but as the rocket climbs higher,
51:35
the tilt becomes more pronounced. This maneuver allows the rocket
51:40
to gradually build horizontal speed while still gaining altitude. By
51:45
the time the rocket reaches space, much of its motion
51:48
is already directed sideways. This is exactly what is needed
51:52
for orbit. The final stage of the rocket is responsible
51:56
for reaching the precise velocity required. Its engines ignite in
52:01
the near vacuum of space, where there is almost no
52:04
atmospheric drag. During this burn, the spacecraft accelerates rapidly. Guidance
52:11
computers carefully adjust the engine's thrust and direction. Every second
52:16
of this burn is calculated with extraordinary precision. Too little
52:20
speed and the spacecraft will fall back into the atmosphere.
52:25
Too much speed and it may escape Earth's gravity entirely.
52:29
Achieving the correct velocity is like threading a needle on
52:33
a cosmic scale. Once the engines shut down, the rocket
52:37
stage may release the spacecraft. Suddenly, the violent acceleration of
52:42
launch disappears. Inside the spacecraft, astronauts or instruments experience weightlessness.
52:50
They float freely inside the cabin. But this weightlessness does
52:54
not occur because gravity has vanished. Gravity is still very strong.
52:59
even hundreds of kilometers above the Earth. Instead, the spacecraft
53:05
and everything inside it are falling together around the planet.
53:09
Since everything is falling at the same rate, there is
53:12
no sensation of weight. From orbit, the Earth moves slowly
53:16
beneath the spacecraft. A full trip around the planet can
53:20
take roughly 90 minutes for objects in low Earth orbit.
53:24
Astronauts aboard the International Space Station see the sun rise
53:27
and set many times during a single day. Cities glow
53:32
softly at night. Lightning storms flash within swirling clouds. The
53:38
thin blue atmosphere appears fragile and delicate from this vantage point.
53:43
Orbit reveals how small and beautiful our planet truly is.
53:47
But reaching orbit is only the beginning of many journeys.
53:51
Some spacecraft remain circling the Earth, Others ignite their engines
53:56
again to travel farther outward. Satellites may climb to higher
54:00
orbits thousands of kilometers above the planet. Spacecraft heading to
54:04
the Moon or Mars accelerate beyond Earth's gravitational hold entirely.
54:09
Each mission begins with the same fundamental challenge. Achieving the
54:14
speed necessary to leave the surface of the Earth. From
54:18
the outside, a rocket launch may appear to be a
54:20
simple vertical ascent. But the true goal of the rocket
54:25
is something more subtle. Not just height, but speed. Speed
54:31
great enough to circle the planet. Speed great enough to
54:35
escape gravity. Speed great enough to carry human exploration deeper
54:40
into the solar system. And once that speed is achieved,
54:44
the door to the rest of the cosmos begins to open.
54:48
In the next part of our journey, we will explore
54:50
some of the most famous rocket launches in history, moments
54:54
when humanity first crossed new frontiers on its path toward
54:58
the stars. Throughout the history of space exploration, certain rocket
55:04
launches have stood out as turning points, moments when humanity
55:08
pushed beyond previous limits, moments when technology, courage and imagination
55:15
came together to send machines and sometimes people far beyond
55:18
the surface of the Earth Among the many rockets that
55:22
have lifted humanity towards space, a few have become especially famous.
55:27
Their launches are remembered not only for their engineering brilliance,
55:31
but also for the way they changed our understanding of
55:34
what is possible. Tonight, we will quietly visit three of
55:38
the most remarkable rockets ever built. The Saturn V, the
55:43
Space Shuttle, and the Falcon 9. Each represents a different
55:48
era in the story of spaceflight. The story of the
55:51
Saturn V begins during one of the most ambitious periods
55:55
in human history. In the 1960s, the United States and
56:00
the Soviet Union were competing in what became known as
56:04
the Space Race. Both nations were determined to demonstrate their
56:08
technological capabilities by exploring space. In 1961, US President John F.
56:16
Kennedy announced a bold goal. Human beings would land on
56:20
the moon before the end of the decade. To achieve
56:24
that goal, engineers needed a rocket far more powerful than
56:28
anything that had ever been built before. The result was
56:31
the Saturn V. The Saturn V remains one of the
56:35
largest and most powerful rockets ever constructed. Standing about 110
56:41
meters tall, it was taller than many skyscrapers. Fully fueled,
56:46
it weighed nearly 3,000 tons. Yet this enormous machine was
56:50
designed to do something extraordinary, carry astronauts all the way
56:55
to the moon. At liftoff, the Saturn V's first stage
56:59
ignited five massive F1 engines. These engines burned refined kerosene
57:05
and liquid oxygen, producing an immense column of fire beneath
57:09
the rocket. Together, they generated about 35 million newtons of thrust.
57:16
The sound of a Saturn V launch could be heard
57:19
many kilometers away. The ground itself seemed to tremble as
57:23
the rocket rose slowly into the sky. The Saturn V
57:27
flew a total of 13 times, and every launch was successful.
57:32
Among these missions were the famous Apollo moon landings. In
57:36
July 1969, a Saturn V carried the Apollo 11 spacecraft
57:42
into orbit. Inside the spacecraft were astronauts Neil Armstrong, Buzz
57:47
Aldrin and Michael Collins. Several days later, Armstrong and Aldrin
57:53
became the first humans to walk on the moon. The
57:56
rocket that carried them there had lifted them from Earth
57:59
with the power of millions of kilograms of burning fuel.
58:03
Even today, watching footage of a Saturn V launch can
58:07
feel awe-inspiring. It remains a symbol of one of humanity's
58:12
greatest achievements. After the Apollo era ended, space exploration began
58:17
to evolve in a new direction. Instead of building a
58:20
new rocket for every mission, engineers began thinking about reusable spacecraft.
58:26
The idea was simple but ambitious. If parts of the
58:30
launch system could return safely to Earth and fly again,
58:34
space travel might become more affordable and frequent. This vision
58:38
led to the creation of the Space Shuttle. The space
58:41
shuttle was unlike any rocket that had come before. Rather
58:45
than a single rocket carrying a capsule, the shuttle consisted
58:49
of several parts working together. At the centre was the orbiter,
58:54
a winged spacecraft that looked somewhat like an aeroplane. Attached
58:58
to the orbiter were two large solid rocket boosters, and
59:02
beneath it all sat a massive orange external fuel tank.
59:07
During launch, the shuttle's main engines and the two boosters
59:10
ignited together. The result was a spectacular column of flame
59:15
and smoke as the shuttle climbed into the sky. The
59:18
shuttle's solid rocket boosters were extremely powerful. They provided most
59:23
of the thrust during the first two minutes of flight.
59:27
Once their fuel was exhausted, the boosters separated from the
59:30
shuttle and parachuted back into the ocean, where they were
59:34
recovered and refurbished for future missions. Meanwhile, the shuttle's main
59:39
engines continued firing, drawing fuel from the external tank. After
59:44
reaching orbit, the empty tank detached and burned up in
59:47
the atmosphere. Only the orbiter remained in space. The most
59:52
remarkable feature of the space shuttle was its ability to
59:55
return to Earth and land like an aircraft. After completing
1:00:00
its mission in orbit, the shuttle would re-enter the atmosphere
1:00:03
and glide toward a runway. Its heat-resistant tiles protected the
1:00:08
spacecraft from the intense temperatures of re-entry. Eventually, the shuttle
1:00:12
would land gently on the runway, ready to be prepared
1:00:15
for another flight. This made it the first partially reusable
1:00:19
space transportation system. Between 1000, 981 and 2011, the space
1:00:28
shuttle flew 135 missions. During that time, it helped build
1:00:34
the International Space Station, launched major scientific satellites, and carried
1:00:40
astronauts from many countries into orbit. The shuttle also launched
1:00:44
the Hubble Space Telescope, one of the most important observatories
1:00:48
ever placed in space. Hubble has transformed our understanding of
1:00:52
the universe, capturing images of distant galaxies, nebulae, and cosmic
1:00:58
phenomena that were once beyond our reach. In more recent years,
1:01:02
another rocket has become famous for a different reason. The
1:01:06
Falcon 9, developed by the company SpaceX. Unlike most rockets
1:01:11
of the past, Falcon 9 was designed with a clear
1:01:14
goal in mind. Reusability. Engineers wanted to build a rocket
1:01:20
whose first stage could return to Earth and land safely
1:01:23
after launch. At first, this idea seemed almost impossible. Landing
1:01:29
a rocket vertically after traveling to space required extremely precise control.
1:01:35
But after many tests and experiments, SpaceX achieved a historic breakthrough.
1:01:41
In 2015, a Falcon 9 booster successfully returned to Earth
1:01:45
and landed upright on a landing pad. The sight of
1:01:49
a tall rocket stage descending from the sky and touching
1:01:52
down gently was unlike anything seen before in spaceflight. Later
1:01:57
landings occurred on floating platforms in the ocean. The boosters
1:02:01
would fire their engines during descent, slowing themselves before landing vertically.
1:02:07
This achievement changed the economics of rocket launches. Instead of
1:02:12
discarding the most expensive part of the rocket after each flight,
1:02:16
the booster could be refurbished and flown again. Falcon 9
1:02:20
has now completed hundreds of launches, carrying satellites, cargo and
1:02:25
astronauts into orbit. It is used to supply the International
1:02:29
Space Station and launch large networks of communication satellites. Its
1:02:34
reusable boosters have demonstrated that rockets can operate more like aircraft, returning,
1:02:40
landing and flying again. This approach has dramatically reduced the
1:02:45
cost of reaching space. Each of these rockets represents a
1:02:49
different chapter in the story of spaceflight. The Saturn V
1:02:53
showed that humanity could reach the Moon. The Space Shuttle
1:02:58
demonstrated that spacecraft could be reused and operate as orbital vehicles.
1:03:03
Falcon 9 introduced a new era of reusable rocket boosters
1:03:07
and commercial spaceflight. Together, they illustrate how rocket technology continues
1:03:13
to evolve, from enormous expendable rockets of the past to
1:03:17
increasingly efficient and reusable systems of the present. Yet the
1:03:22
story of rockets is far from finished. Engineers and scientists
1:03:26
around the world are already designing new vehicles that may
1:03:29
travel even farther. Some rockets may carry humans back to
1:03:33
the moon. Others may one day journey to Mars. And
1:03:38
as technology continues to improve, the dream that once seemed
1:03:42
impossible leaving Earth and exploring the cosmos moves steadily closer
1:03:46
to reality. In the next part of our journey, we
1:03:50
will explore one of the most exciting developments in modern spaceflight.
1:03:55
Rockets that not only reach space, but return safely to Earth,
1:03:59
ready to launch again. As we look toward the future,
1:04:04
the story of rocket launches is far from finished. In fact,
1:04:09
it may only be beginning. For more than half a century,
1:04:13
rockets have carried satellites, scientific instruments, and astronauts into orbit
1:04:19
around the Earth. They have allowed us to study distant planets,
1:04:23
observe the universe through space telescopes, and maintain the delicate
1:04:27
network of satellites that supports modern life. But the rockets
1:04:31
of the future may take humanity even farther. Beyond Earth orbit.
1:04:37
Beyond the moon. Perhaps one day even to other worlds.
1:04:42
Engineers around the world are already designing the next generation
1:04:45
of launch systems machines far more powerful, efficient, and reusable
1:04:51
than anything that has come before. Among these new vehicles,
1:04:55
one rocket in particular has captured global attention. Starship. Starship
1:05:00
is being developed as one of the largest rockets ever constructed.
1:05:05
When fully assembled with its massive booster stage, the system
1:05:08
will stand nearly 120 meters tall, making it even taller
1:05:13
than the Saturn V. The rocket consists of two main parts.
1:05:18
The super heavy booster, which provides the thrust needed to
1:05:22
leave the launch pad, and the Starship spacecraft, which sits
1:05:26
on top and carries cargo or astronauts into orbit and beyond.
1:05:31
Unlike most previous rockets, the entire system is designed to
1:05:35
be fully reusable. After launch, the booster is intended to
1:05:39
return to Earth and land vertically. The Starship spacecraft itself
1:05:44
may also return and land in a similar way. If successful,
1:05:49
Both parts of the rocket could be reused again and again.
1:05:52
This could dramatically reduce the cost of launching missions into space.
1:05:57
Starship is designed to carry enormous payloads. It may be
1:06:01
capable of lifting more than 100 tonnes of cargo into orbit.
1:06:06
That kind of capacity opens the door to new possibilities.
1:06:10
Large space stations could be assembled more easily. Massive scientific
1:06:14
observatories could be launched in a single mission. and long-distance
1:06:18
spacecraft capable of traveling to other planets could be built
1:06:22
and fueled in orbit. But one of the most exciting
1:06:25
goals associated with Starship is something even more ambitious. Human
1:06:31
missions to Mars. Mars has fascinated humanity for centuries. Through telescopes,
1:06:37
astronomers have studied its reddish surface in changing seasons. Robotic
1:06:42
spacecraft have explored its deserts, mountains, and ancient riverbeds. We
1:06:48
now know that Mars once had liquid water flowing across
1:06:52
its surface billions of years ago. Today, it remains one
1:06:57
of the most promising places in the solar system to
1:06:59
search for evidence of past life. But sending humans to
1:07:03
Mars is an enormous challenge. The journey requires traveling tens
1:07:08
of millions of kilometers through space. Astronauts would spend many
1:07:12
months in transit before reaching the planet. To make such
1:07:16
missions possible powerful and reliable rockets are essential. Starship is
1:07:22
one of the vehicles that may help make this dream
1:07:24
a reality. Beyond chemical rockets like Starship scientists are also
1:07:29
exploring entirely new types of propulsion. One of the most
1:07:33
intriguing possibilities is the nuclear thermal rocket. Unlike traditional rockets
1:07:38
that burn chemical fuel nuclear rockets use the energy produced
1:07:43
by a nuclear reactor In a nuclear thermal engine, hydrogen
1:07:47
propellant is heated to extremely high temperatures inside a reactor core.
1:07:52
The hot gas then expands through a nozzle, producing thrust.
1:07:56
Because nuclear reactions release enormous amounts of energy, these engines
1:08:01
can be far more efficient than chemical rockets. This means
1:08:05
spacecraft could travel faster while carrying less fuel. For long
1:08:09
journeys through the solar system, this advantage could be very important.
1:08:14
Nuclear propulsion has been studied for decades. In the 1960s
1:08:19
and 1970s, engineers in the United States conducted several experiments
1:08:24
with prototype nuclear rocket engines. The results were promising. However,
1:08:30
the program was eventually cancelled before the technology could be
1:08:33
used in space missions. Today, interest in nuclear propulsion is
1:08:38
growing once again. Several space agencies are studying how these
1:08:42
engines might help send astronauts to Mars more quickly. Shorter
1:08:46
travel times would reduce the risks associated with long-duration spaceflight.
1:08:51
It could also make future missions safer and more practical.
1:08:55
Another idea being explored involves in-orbit refueling. Instead of launching
1:09:00
a spacecraft with all its fuel from Earth, smaller tanker
1:09:03
rockets could deliver fuel to the spacecraft once it is
1:09:06
already in orbit. This would allow spacecraft to begin long
1:09:10
journeys with full fuel tanks without requiring a single enormous
1:09:15
rocket at launch. Such techniques may become essential for deep
1:09:19
space missions in the future. They could enable large interplanetary
1:09:23
spacecraft to assemble and prepare for their journeys while orbiting
1:09:27
the Earth. As rocket technology advances, the pace of space
1:09:31
exploration may accelerate dramatically. In the early decades of spaceflight,
1:09:37
launches were rare and extremely expensive. Today, rockets launch far
1:09:42
more frequently. Reusable boosters, New propulsion technologies and improved engineering
1:09:49
methods are steadily lowering the cost of reaching space. Each
1:09:53
improvement makes it easier to explore new destinations. The Moon
1:09:57
may soon host permanent human research stations. Mars may become
1:10:02
the next great frontier for exploration. And beyond Mars lie
1:10:06
countless other worlds waiting to be studied. Yet even as
1:10:10
rockets grow more powerful, the basic idea remains the same
1:10:14
as it was centuries ago. A rocket moves by pushing
1:10:17
hot gases downward. The reaction pushes the rocket upward. It
1:10:22
is a simple principle, described long ago by Newton's third law.
1:10:27
From this simple law, engineers have built machines capable of
1:10:31
carrying humanity beyond the surface of the Earth. Machines capable
1:10:36
of reaching the moon. Machines capable of exploring the planets.
1:10:41
And perhaps someday, Machines capable of carrying people across the
1:10:45
vast distances between the stars. For now, rockets continue to
1:10:50
rise from launch pads around the world. Each launch represents
1:10:54
a moment of transformation. Fire and thunder lifting machines into
1:10:59
the sky. Carefully engineered technology overcoming the pull of gravity.
1:11:05
And with every launch, humanity takes another small step into
1:11:08
the wider universe. In the final moments of our journey tonight,
1:11:13
we will reflect quietly on what these remarkable machines have
1:11:16
made possible and what adventures may still lie ahead among
1:11:20
the stars. For thousands of years, humanity stood beneath the
1:11:26
night sky and wondered what lay beyond. The stars shimmered
1:11:30
above every civilization that has ever existed. Ancient travellers, poets
1:11:35
and scientists all looked upward, and imagined distant worlds floating
1:11:40
in the darkness. But for most of human history, those
1:11:44
worlds remained forever out of reach. Gravity held us firmly
1:11:49
on the surface of the Earth. The stars belonged to
1:11:52
the sky alone. Then, slowly, something changed. Human curiosity began
1:11:59
to turn into engineering. Ideas turned into machines. And one day,
1:12:04
with fire and thunder, the first rockets rose from the
1:12:08
ground and carried our technology into space. Rockets became the
1:12:12
bridges between Earth and the cosmos. Each launch was more
1:12:16
than just a machine leaving the ground. It was a
1:12:19
doorway opening. A path connecting our small planet to the
1:12:24
vast universe beyond. With rockets, humanity placed satellites around the
1:12:29
Earth that help us communicate across continents. We launched telescopes
1:12:34
that revealed distant galaxies billions of light-years away. We sent
1:12:38
robotic explorers to the Moon, Mars and the outer planets.
1:12:43
And for the first time in history, human beings themselves
1:12:47
left the Earth and travelled into orbit. All of this
1:12:50
began with the simple idea of a rocket pushing fire
1:12:53
downward to rise upward. Yet even after all these achievements,
1:12:58
the journey has only just begun. The rockets we launch
1:13:01
today are only the first steps in a much longer story.
1:13:05
Future rockets may carry astronauts back to the moon. They
1:13:09
may take the first human explorers to Mars. One day,
1:13:14
they might even travel farther still to the icy moons
1:13:16
of Jupiter, the distant worlds of the outer solar system,
1:13:21
or destinations we have not yet imagined. Every rocket launch
1:13:25
reminds us that exploration is part of what makes us human.
1:13:29
We look outward. We ask questions, and we build machines
1:13:33
that allow us to go farther than the generations before us.
1:13:37
But for tonight, our journey can slow down. The launch
1:13:41
pads grow quiet again, the engines fall silent, and the
1:13:46
rockets that carried us through this story drift gently into
1:13:49
orbit around the Earth. Imagine them there now, circling the
1:13:54
planet far above the clouds, gliding through the quiet darkness
1:13:59
of space, Below them, the Earth turns slowly beneath the stars.
1:14:04
As you relax and prepare for sleep, you might imagine
1:14:07
yourself watching a rocket launch from a quiet distance. The
1:14:11
engines ignite. A bright column of flame rises into the night.
1:14:17
The rocket climbs higher and higher until it becomes only
1:14:20
a small point of light moving among the stars. And then, slowly,
1:14:26
it disappears into the darkness of space. leaving behind only
1:14:30
the quiet sky above. Thank you for joining this peaceful
1:14:34
journey through the science of rocket launches. Wherever you are
1:14:38
in the world tonight, I hope the story helped your
1:14:41
mind drift gently among the stars. Now it's time to rest.
1:14:46
Let your breathing slow, close your eyes, and imagine the
1:14:51
endless universe waiting quietly beyond the earth. In a moment,
1:14:56
soft ambient music will begin. Let that music guide you
1:15:01
into a calm and restful sleep. Good night, and sleep well.
1:16:05
Speaker 2: Thank you for watching. Thank you. Thank you. Thank you
1:18:05
for watching. Thank you. This is the first time that
1:19:53
I have seen this. I have never seen anything like this.
1:20:32
Thank you. Thank you for watching. Thank you. Thank you.
1:23:50
Thank you for watching. This is the first time that
1:24:25
I have seen this kind of thing. you you you
1:26:04
you you you Thank you for watching. Thank you for watching.
1:28:25
Thank you. Thank you. Thanks for watching! This is the
1:29:36
first time I've seen this in real life. This is
1:29:37
the first time I've seen this in real life. Thank
1:30:09
you for watching. you you you Thank you. This is
1:33:00
the first time that I have seen this kind of thing.
1:34:09
you you you.
1:34:55
Speaker 1: Thank you.
1:35:20
Speaker 2: Thank you for watching. Thank you. you you you Thank you.
1:38:13
Thank you. Thank you. Thank you. you you you Amen.
1:40:40
Thank you. Thank you for watching. Thank you for watching.
1:42:05
you you you Thank you. Thank you. Thank you for watching.
1:47:22
Thank you for watching. you you you Thanks for watching!
1:49:43
Thank you for watching. Thank you. Thank you. you you
1:53:36
you you you Thank you. Thank you for watching. Thank
1:56:02
you for watching. Thanks for watching! Thank you. Thank you.
2:00:25
Thank you. Thank you. Thank you for watching. Thank you
2:01:47
for watching. Thank you for watching!