Robert Hutchings Goddard Essay

Robert Hutchings Goddard is an American rocketry pioneer; he is considered the father of modern rocket propulsion. In 1926, Goddard had constructed and successfully tested the first rocket that uses liquid fuel. The flight of Goddard’s rocket on March 16, 1926, at Auburn, Massachusetts, was as significant step to improving rockets. The first culture that started to experiment with rockets was the Chinese, the date reporting the first use of rockets was in 1232. The earliest rockets were used by the Chinese to defend their home from the Mongols by shooting a barrage of "arrows of flying fire.". They started to fill gunpowder into bamboo tubes, then they put the gunpowder filled tubes on arrows and began to launch them they eventually found that the gas can launch the arrows. When the

powder was ignited, the rapid burning of the powder produced smoke, fire and gas that escaped out the open end and produced a thrust which launched the rocket in the air. The stick on the rocket was a simple guidance system that kept the rocket headed in one direction as it flew through the air. It is not known how effective these arrows of flying fire were as weapons, but their psychological effects on the Mongols must have been extraordinary since they have never seen anything like this. The way rockets have improved over time is the rockets are now able to carry payloads like an explosive or a human into space. The most destructive payload that is in the world is the Tsar Bomba which has the blast radius of a yield of megaton TNT. The most advance rocket that can take humans to space is coming in 2018 it’s called the SLS, will have 8.5 million pounds of thrust, its goal is to take humans into deep space. The biggest use for rockets in the 21st century is for war. The main use for the rocket in war is to propel explosive payloads to designated targets. Rockets are also used for entertainment such as fireworks, which we use to celebrate holidays like the fourth of July. NASA (National Aeronautics and Space Administration) Builds rockets to send humans to space for the United States Government, their upcoming project will be to send a team of astronauts to explore mars. Scientific uses of rockets include satellites, weather, and communication. Rockets are used to launch satellites and Space Shuttles into space. Their powerful engines allow spacecraft to be blasted into space at great speeds, putting them into the orbit. A satellite is an artificial body placed in orbit around the earth or moon or another planet in order to collect information or for communication. This is how scientist gather information about our world and other planets to expand our knowledge of the galaxy and to improve our technology. A new rocket called Cape Canerval will cost the U.S $11 billion dollars. This new GOES-R spacecraft will track U.S. weather such as: hurricanes, tornadoes, flooding, volcanic ash clouds, wildfires, lightning storms, even solar flares. Indeed, about 50 TV meteorologists from around the country met on the launch site including along with 8,000 space program workers and guests. Rockets also help the way we communicate by sending satellites to space, so we can talk with other around the world. A rocket in its simplest form is a chamber enclosing a gas under pressure. An opening at one end of the chamber allows the gas to escape from it, and in doing so provides a thrust that propels the rocket in the other direction. An example of this is a balloon when u fill a balloon with air. The air in the balloon is being compressed by the rubber walls which causes the air to go out through the hole and propel the balloon the opposite direction. Like all objects, rockets are governed by Newton's Laws of Motion. The First Law describes how an object acts when no force is acts upon it. So, rockets stay still until a force is applied to move them. Likewise, once rockets are in motion, they won't stop until a force that stops them is applied. Newton's Second Law says that the more mass an object has, the more force is needed to move the object. A larger rocket will need stronger forces like more fuel to make it accelerate. The space shuttles launched by NASA required seven pounds of fuel for every pound of payload they carry. Newton's Third Law states that "every action has an equal and opposite reaction". In a rocket, burning fuel creates a push on the front of the rocket propelling it forward. This creates an equal and opposite push on the exhaust gas of the rocket. There are multiple rocket fuels used to propel rockets into space such as Petroleum, Cryogenic, and Hypergolic. Petroleum fuels are refined from crude oil and are a combination of complex hydrocarbons, i.e. organic compounds containing only carbon and hydrogen. The petroleum used as rocket fuel is a type of extremely refined kerosene, called RP-1 in the United States. Petroleum fuels are used in combination with liquid oxygen as the oxidizer. Kerosene delivers a specific impulse considerably less than cryogenic fuels, but it is generally better than hypergolic propellants. Cryogenic fuels propellants are liquefied gases stored at very low temperatures, most frequently liquid hydrogen (LH2) as the fuel and liquid oxygen (LO2 or LOX) as the oxidizer. Because of the very low temperatures of cryogenic propellants, they are difficult to store for long periods of time. For this reason, they are not desirable for use in military rockets that must be kept launch ready for months at a time. Hypergolic propellants are fuels and oxidizers that ignite spontaneously on contact with each other and require no ignition source. The easy start and restart capability of hypergols make them ideal for spacecraft maneuvering systems like space shuttles. Also, since hypergols remain liquid at normal temperatures, they do not pose a storage problem like cryogenic propellants.

Hypergols are highly toxic and must be used with extreme care. Hypergolic fuels commonly include hydrazine, monomethyl hydrazine (MMH) and unsymmetrical dimethyl hydrazine (UDMH). Hydrazine gives the best performance as a rocket fuel for most situations. Rockets have improved greatly since the time of Robert Hutchings Goddard, now they are able to go further and faster than ever before. The SLS will be NASA’s first exploration-class vehicle that will take Astronauts to mars for the first time in history. It will expand our reach in the solar system, launching crews aboard the new Orion spacecraft to explore multiple, deep-space destinations including mars. A fleet of robotic spacecraft and rovers are already on and around Mars, but to fly to and land humans safely on Mars requires a next-generation spacecraft this is where the SLS will come into play too complete that job. This “Rockets” essay helped me learn about the science of how rockets work such as the propellants used and how newton’s laws of motion affect rockets. Researching rockets led to mea learning about the culture of rockets and how they were first invented and used by the Chinese against the Mongols to defend their

home.