Three crew members of the US space shuttle Atlantis strapped into their launch positions practice a countdown at the Kennedy Space Center in preparation for their September 25 1997 liftoff Earth There was a lot to explore and research and rocket science would help get people there With the help of rockets multiton spacecraft can be blasted out of the atmosphere at tens of thousands of 6 roCket sCIenCe and spaCeCraft fundamentals
IntroduCtIon miles per hour defying the pull of gravity The first space capsules could fit just one astronaut with no room to move around Later as technology improved spacecraft were able to accommodate crews who worked together to operate the craft and perform research Ongoing advances will allow scientists to design ever-more complex spacecraft capable of traveling even faster and farther shedding light on more of the mysteries of the universe 7
Rocket PoweR Without rocket science humans would know a lot less about space than they know today What are the basics of rocket science There’s a lot to consider when designing and building a rocket for use in outer space For example there is no air in space It is a vacuum Therefore jet engines that use oxygen from the air to burn fuel cannot be used in space They work only in Earth’s atmosphere Rockets on the other hand carry their own oxygen supply This allows them to operate outside of Earth’s atmosphere NEWTON’S THIRD LAW To understand the basics of rocket science it helps to think about Isaac Newton’s laws of motion A physicist and math ematician Newton came up with three important rules that describe how the motion of objects can be changed by forces Newton’s third law states that for every action there is an equal and opposite reaction For example you kick a ball That’s an action of your foot applying a force to the ball 8 roCket sCIenCe and spaCeCraft fundamentals Chapter 1
roCket power A Titan II rocket lifts off from an underground silo The Titan II first developed as a missile served as a launch vehicle for the Gemini manned spacecraft missions and military and civilian satellites You cannot see it but the ball is also exerting a force back on your foot The reaction force is equal in size and opposite in direction to the action force The propulsion of a rocket also depends on an action and reaction The process begins with the burning of fuel in the engine which creates hot gases as exhaust The action is the engine pushing out the gases The reaction is the rocket moving in the opposite direction In other words the rocket pushes the exhaust backward and the exhaust pushes the rocket forward Scientists worked for many years putting Newton’s laws to work The idea that rockets could be used for space exploration spurred much experimentation in the late nineteenth and early twentieth centuries Pioneering sci entists such as Konstantin E Tsiolkovsky of Russia Robert H Goddard of the United States and Hermann Oberth of Germany laid the foundations of modern rocketry during these years Goddard launched the world’s first successful 9
