Information taken from Wikipedia and Books by Stephen and Lucy Hawking



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What is a rocket?

A rocket is a missile, spacecraft, aircraft or other vehicle that obtains thrust from a rocket engine. Rocket engine exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction. Rocket engines push rockets forward simply by throwing their exhaust backwards extremely fast.

While comparatively inefficient for low speed use, rockets are relatively lightweight and powerful, capable of generating large accelerations and of attaining extremely high speeds with reasonable efficiency. Rockets are not reliant on the atmosphere and work very well in space.


Who made the first rockets?

The Chinese made the first rockets about 1000 years ago but they were more like fireworks than today’s space rockets. They were flaming arrows that were fired from a basking using gunpowder.



When did the first liquid – fuel rocket fly?

In 1926, American Robert Goddard launched a 3.5 metre long rocket. It flew about as high as a two – storey house, nowhere near outer space, and landed 56 metres away. The flight lasted just two and a half seconds.



Who built a rocket for war?

Wernher von Braun invented the V2, a rocket missile used by the Germans in World War II. After the war, von Braun moved to the United States with the new American space programme.



Why do we need rockets?

Rockets are important for space travel. They are the only achiness powerful enough to launch things into space, such as satellites, probes and people. Rockets have carried all the parts needed to build space stations up.



How fast can a rocket go?

To escape from Earth’s gravity, a rocket has to reach 40,000 kph – almost 20 times faster than Supersonic Concorde. Once it is out in the space, the rocket drops down to around 29,000 kph to stay in orbit.



Why do rockets fall to pieces?

Rockets are made in stages, or pieces. Usually, there are three stages, made up of the fuel tank, rocket engines and the sitting area where the astronauts sit and work. The fuel tank contains fuel through which the rocket launches. After this the fuel tank is dropped into the sea and is picked up by other astronauts. The rocket boosters help the rockets to launch and boost up the rocket.



How do rocket engines work?

A rocket engine is not like a conventional engine.  A conventional engine ignites fuel which then pushes on some pistons, and it turns a crank.  Therefore, it uses rotational energy to turn the wheels of the vehicle.  Electric motors also use rotational energy to turn fans, and spin disks.  A rocket engine does not use rotational energy to run.  They are reaction engines.  The principle of it is that the fuel contained within the body of the rocket goes through a chemical reaction as it comes out of the end of the rocket.  This reaction then causes thrust and propels the rocket forward.  This is an example of one of Sir Isaac Newton's fundamental laws.  "For every action, there is an equal and opposite reaction"



Solid fuel rockets are the first rockets to be recorded in history.  They were first invented in ancient China, and have been used ever since (How Rocket Engines Work.)  The chemical make up of a solid rocket fuel is very similar to the chemical makeup of gunpowder.  However, the exact chemical make up is not the same.  To make a rocket work, a fast burning nonexclusive fuel is needed.  Gunpowder explodes, making it unusable.  So the chemical composition was altered to make it burn fast, but not explode.  One of the biggest problems with solid fuel rocket engines is that once started, the reaction cannot be stopped or restarted.  This makes them considered uncontrollable.  Therefore, solid fuel rockets are more widely used for missiles, or as booster rockets.



                            

                    

The first liquid fuel rocket was produced by Robert Goddard in 1926 (How Rocket Engines Work.)  The idea of liquid fueled rocket is easy to grasp.  A fuel and an oxidizer ,in Goddards case he used gasoline and liquid oxygen, are pumped into a combustion chamber.  A reaction takes place, and it expands propelling the rocket forward.  The expanding gas is then forced through a nozzle that makes them accelerate to a higher velocity (How Rocket Engines Work.)


                   

What is rocket fuel made of?

If you mean the stuff that is used in the giant fuel tank that is attached to a departing space shuttle, then it is almost entirely liquid O2 (liquid oxygen).


Spacesuit

What Is a Spacesuit?
A spacesuit is more than clothes astronauts wear in space. The suit is really a small spacecraft. It protects the astronaut from the dangers of being outside in space.
Why Do Astronauts Need Spacesuits?

Spacesuits help astronauts in many ways. The suits protect astronauts from getting too hot or cold. Spacesuits also give astronauts oxygen to breathe while they are working in space. The suits hold water to drink. They also keep astronauts from getting hurt by space dust. Space dust may not sound very dangerous. But when it moves faster than a bullet, the dust can hurt someone. The suits even have special gold-lined visors to protect eyes from bright sunlight.


What Are the Parts of a Spacesuit?

A spacesuit is made up of many parts. One part covers the astronaut's chest. Another part covers the arms and connects to the gloves. The helmet protects the head. And the last part covers the astronaut's legs and feet. Some parts of the suit are made of many layers of material. Each layer does something different. Some keep oxygen in the suit while others protect astronauts from space dust.

Under the suit, astronauts wear another piece of clothing. It covers their body except for the head, hands and feet. Tubes are woven into it. Water flows through the tubes to keep the astronaut cool.

On the back of the spacesuit is a backpack. The backpack holds oxygen so astronauts can breathe. It also removes carbon dioxide that astronauts have breathed out. The backpack also supplies electricity for the suit. A fan moves the oxygen through the spacesuit. A water tank holds the cooling water.



Connected to the back of the suit is a tool called SAFER. SAFER has several small thruster jets. If an astronaut floated away from the space station, he or she could use SAFER to fly back.

Parts of a Spacesuit
NASA spacesuits have many pieces and parts. Learn about the parts and why each piece is important.





Primary Life Support Subsystem
The PLSS is worn like a backpack. It provides astronauts many of the things they need to survive on a spacewalk. Its tanks supply oxygen for the astronauts to breathe. It removes exhaled carbon dioxide. It contains a battery for electrical power.

The PLSS also holds water-cooling equipment, a fan to circulate oxygen and a two-way radio. A caution and warning system in this backpack lets spacewalkers know if something is wrong with the suit. The unit is covered with protective cloth layers.








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