- "A good rule for rocket experiments to follow is this: always assume that it will explode."
- –Astronautics Magazine 1937
Rockets are devices capable of self-propelling through the air (or space), and thus independent of initial acceleration. Their invention opens up whole new avenues of development in military technology.
But more than that, the development of Rocketry also proves possible that humanity can leave the confines of its home planet and fly into space! The Apollo Program opens up the late-game race to conquer space and win a Technological victory.
The earliest known rocket flight is a bit contested, although it is generally believed that it occurred sometime around 1230 A.D. in China, during a military operation. The first actual recorded flight did occur in China in 1264 as part of an internal-combustion firework. These early rockets used solid fuel, usually gunpowder, and did not fly very far, perhaps only 2000 feet.
The invention of modern rocketry can be attributed directly to Professor Robert Goddard when he postulated that fuel should be burned in a small, separate combustion chamber, the rocket should be built in separable stages, and that the exhaust speed could be increased by using a special hour-glass shaped nozzle called a De Laval nozzle. Up to this point rockets burned all their fuel in one large solid chamber and weren't capable of going exceptionally fast or travelling intercontinental distances.
Rockets now commonly use a combination of liquid fuels which are able to accelerate the rocket to hypersonic speeds with great efficiency for a relatively low price. Besides their obvious military use to propel warheads across great distances, rockets are also used for fireworks, ejection seats, scientific atmospheric research, and of course, spaceflight.