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Rocket

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A rocket is an elongated flying vehicle designed to accelerate using a rocket engine.

Soyuz TMA-9 launch
Soyuz TMA-9 launch

This vehicle is unique because it does not rely on surrounding air to function. Instead, it generates thrust by reacting to exhaust expelled at extremely high speeds.

Rocket thrust
Rocket thrust

Because rockets carry their own propellant, they do not need to breathe oxygen from the atmosphere. This capability allows them to operate in the vacuum of space. In fact, rocket engines actually operate more efficiently outside of the Earth's atmosphere.

A balloon with a tapering nozzle
A balloon with a tapering nozzle

By using multistage designs, rockets can reach escape velocity to leave Earth entirely.

To understand the mechanism, one must look at how chemical rockets create power. Most high-power rockets use the combustion of fuel with an oxidizer to create high-speed exhaust.

Viking 5C rocketengine
Viking 5C rocketengine

This process can involve several different types of propellant systems. Some rockets use a monopropellant, which is a single liquid fuel that breaks apart when it hits a catalyst. Others use hypergolic propellants, which are two liquids that react spontaneously upon contact. Many liquid-propellant rockets use two separate liquids, such as kerosene and liquid oxygen, which require an ignition source to react. There are also solid fuel rockets and hybrid systems that combine solid fuel with liquid or gaseous oxidizers. These systems store massive amounts of energy that are released during combustion.

Engineers use various methods to control a rocket's flight path and stability. Some rockets use momentum wheels or auxiliary reaction engines to change direction. Others use gimballed thrust, which means the engine nozzle can tilt to steer the vehicle. Pilots and computers can also control flight by deflecting the exhaust stream or adjusting the propellant flow. Some rockets even use spin to maintain stability. If no active control is used, the rocket may simply follow a ballistic trajectory under the influence of gravity. These different methods allow rockets to perform complex maneuvers in both air and space.

Rocket technology has a long history dating back to 13th-century China.

Oldest depiction of rocket arrows
Oldest depiction of rocket arrows

During the Song dynasty, gunpowder-powered rockets and early multiple rocket launchers were developed. The Mongols later spread this technology to the Middle East and Europe. In the 14th century, the Chinese military treatise *Huolongjing* described the 'fire-dragon issuing from the water,' which is considered the first known multistage rocket. By the late 18th century, the Kingdom of Mysore in India developed the first successful iron-cased rockets.

Rocket warfare
Rocket warfare

These innovations led to the British Congreve rocket in 1804, which significantly increased the effective range of military rockets.

Modern rocketry was transformed by several key scientific breakthroughs in the 20th century. In 1926, Robert Goddard launched a rocket using liquid propellants instead of gunpowder.

Goddard and Rocket
Goddard and Rocket

He also attached a supersonic de Laval nozzle to his combustion chamber. This nozzle turns hot gas into a highly directed, hypersonic jet, which increased engine efficiency from 2% to 64%. During World War II, the German V-2 rocket became a major technological milestone.

Bundesarchiv Bild 141-1880, Peenemünde, Start einer V2
Bundesarchiv Bild 141-1880, Peenemünde, Start einer V2

In 1944, a V-2 became the first artificial object to cross the Kármán line and enter space. This era of development provided the foundational technology used to eventually reach the Moon.

Today, rockets serve a vast array of industrial, scientific, and recreational purposes. They are essential launch vehicles for artificial satellites and human spaceflight.

Missions like the Apollo program used rocket technology to explore the Moon and beyond.

Rockets are also used for military missiles, ejection seats, and even small fireworks. The ability to reach high altitudes allows scientists to study cosmic rays and the temperature of the atmosphere. This versatility makes the rocket one of the most important tools in modern science.

Ultimately, the study of rockets connects the fields of chemistry, physics, and engineering. The development of the Tsiolkovsky rocket equation helped scientists understand the relationship between mass and velocity.

Tsiolkovsky rocket equation
Tsiolkovsky rocket equation

As we continue to improve engine efficiency and propellant types, our ability to explore the solar system grows. From the early fire arrows of China to the massive launch pads of today, rockets remain our primary way to reach the stars.

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🖼️ Images & Media (28)
File:Soyuz TMA-9 launch.jpg
Soyuz TMA-9 launch.jpg
File:Oldest depiction of rocket arrows.jpg
Oldest depiction of rocket arrows.jpg
File:Rocket warfare.jpg
Rocket warfare.jpg
File:William Congreve at Copenhagen 1807.jpg
William Congreve at Copenhagen 1807.jpg
File:Goddard and Rocket.jpg
Goddard and Rocket.jpg
File:RIAN archive 303890 A battery of Katyusha during the 1941-1945 Great Patriotic War.jpg
RIAN archive 303890 A battery of Katyusha...
File:Bundesarchiv Bild 141-1880, Peenemünde, Start einer V2.jpg
Bundesarchiv Bild 141-1880, Peenemünde,...
Apollo 15 launch.ogv
File:Viking 5C rocketengine.jpg
Viking 5C rocketengine.jpg
File:Gas Core light bulb.png
Gas Core light bulb.png
File:Pendulum rocket fallacy.png
Pendulum rocket fallacy.png
File:Trident II missile image.jpg
Trident II missile image.jpg

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