Rockets. History of Rockets. The first rockets appear in ancient china. The Chinese began...

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Rockets Rockets

Transcript of Rockets. History of Rockets. The first rockets appear in ancient china. The Chinese began...

RocketsRockets

History of Rockets. History of Rockets.

The first rockets appear in ancient china. The Chinese began experimenting with

gunpowder-filled tubes attached to arrows and launched them with bows.

They discovered that these gunpowder tubes could launch themselves just by the power produced from the escaping gas. The true rocket was born.

First manned rocket flightFirst manned rocket flight

In the 16th century a lesser-known Chinese official named Wan-Hu assembled a rocket- powered flying chair. Attached to the chair were two large kites, and fixed to the kites were forty- seven fire-arrow rockets.

On the day of the flight, Wan-Hu sat himself on the chair and gave the command to light the rockets. Forty-seven rocket assistants, each armed with torches, rushed forward to light the fuses. In a moment, there was a tremendous roar accompanied by billowing clouds of smoke. When the smoke cleared, Wan-Hu and his flying chair were gone. No one knows for sure what happened to Wan-Hu.

In Our HistoryIn Our History

During the end of the 18th century and early into the 19th, rockets experienced a brief revival as a weapon of war. The success of Indian rocket barrages against the British in 1792 and again in 1799 caught the interest of an artillery expert, Colonel William Congreve. Congreve set out to design rockets for use by the British military.

The Congreve rockets were highly successful in battle. Used by British ships to pound Fort McHenry in the War of 1812, they inspired Francis Scott Key to write "the rockets' red glare," words in his poem that later became The Star- Spangled Banner.

However the accuracy was still poor and the rockets were eventually discarded for artillery.

Modern Rocketry BeginsModern Rocketry Begins

In 1898, a Russian schoolteacher, Konstantin Tsiolkovsky (1857-1935), proposed the idea of space exploration by rocket.

In a report he published in 1903, Tsiolkovsky suggested the use of liquid propellants for rockets in order to achieve greater range.

Tsiolkovsky stated that the speed and range of a rocket were limited only by the exhaust velocity of escaping gases.

For his ideas, careful research, and great vision, Tsiolkovsky has been called the father of modern astronautics.

Goddard Goddard

Early in the 20th century, an American, Robert H. Goddard (1882-1945), conducted practical experiments in rocketry.

Goddard achieved the first successful flight with a liquid- propellant rocket on March 16, 1926. Fueled by liquid oxygen and gasoline, the rocket flew for only two and a half seconds, climbed 12.5 meters, and landed 56 meters away in a cabbage

patch

Hermann Oberth Hermann Oberth

Hermann Oberth was the inventor of the german V2 rocket.

The V-2 rocket (in Germany called the A-4) was small by comparison to today's rockets. It achieved its great thrust by burning a mixture of liquid oxygen and alcohol at a rate of about one ton every seven seconds. Once launched, the V-2 was a formidable weapon that could devastate whole city blocks.

Modern rockets. Modern rockets.

Both the US and the Solviet Union noticed the power of the rocket and began to create more and more powerful rockets.

On October 4, 1957, the world was stunned by the news of an Earth-orbiting artificial satellite launched by the Soviet Union (Sputnik I)

But how do rockets work?But how do rockets work?

Have you ever wondered how rockets work in space considering there is nothing to push against to make them move.

Newton’s third law of motion states that for every action there is an equal and opposite reaction.

For example if you throw a ball standing on wheels the ball moves forward and you move backward.

For a RocketFor a Rocket

A rocket shoots its fuel out the back at an incredibly high speed.

This fuel being pushed out the back pushes forward on the rocket.

So rockets actually work better in space because there is no air resistance.

This concept of "throwing mass and benefiting from the reaction" can be This concept of "throwing mass and benefiting from the reaction" can be hard to grasp at first, because that does not seem to be what is happening. hard to grasp at first, because that does not seem to be what is happening.

Rocket engines seem to be about flames and noise and pressure, not Rocket engines seem to be about flames and noise and pressure, not "throwing things." So let's look at a few examples to get a better picture of "throwing things." So let's look at a few examples to get a better picture of

realityreality

: (from www.howstuffworks.com If you have ever shot a shotgun, especially a big 12-gauge shot gun, then you know that it

has a lot of "kick." That is, when you shoot the gun it "kicks" your shoulder back with a great deal of force. That kick is a reaction. A shotgun is shooting about an ounce of metal in one direction at about 700 miles per hour, and your shoulder gets hit with the reaction. If you were wearing roller skates or standing on a skateboard when you shot the gun, then the gun would be acting like a rocket engine and you would react by rolling in the opposite direction.

If you have ever seen a big fire hose spraying water, you may have noticed that it takes a lot of strength to hold the hose (sometimes you will see two or three firefighters holding the hose). The hose is acting like a rocket engine. The hose is throwing water in one direction, and the firefighters are using their strength and weight to counteract the reaction. If they were to let go of the hose, it would thrash around with tremendous force. If the firefighters were all standing on skateboards, the hose would propel them backwards at great speed!

When you blow up a balloon and let it go so that it flies all over the room before running out of air, you have created a rocket engine. In this case, what is being thrown is the air molecules inside the balloon. Many people believe that air molecules don't weigh anything, but they do (see the page on helium to get a better picture of the weight of air). When you throw them out the nozzle of a balloon, the rest of the balloon reacts in the opposite direction.

The Ultimate in FlightThe Ultimate in Flight

The most amazing machine for flight ever created is undoubtedly the space shuttles.

Columbia launched for the first time in 1981. They are carried into space on the back of two

giant rockets that are jettisoned after launch. The shuttle can remain in space for over two

weeks before gliding back to a landing on earth.

Dangers of RocketsDangers of Rockets

Rocket travel is not without its dangers

17 NASA astronauts have not returned to earth

The most recent is Columbia flight STS 107 which killed all 7 astronauts when a heat shield failed on reentry

Personal Rockets?Personal Rockets?

The X Prize was a contest with a 20 million prize to the first group to launch a person into space.

It was won by Burt Rutan flying spaceship one

The FutureThe Future

Currently space tourism is becoming common

For 20 million dollars you can fly on a russian mission to the ISS

Virgin airlines are starting plans for a space plane that will take paying customers into low earth orbit.