Rockets, however, are not merely for entertainment. They have become important in a large number of civilian and military applications.
Rockets are vital and effective weapons of warfare.
Large-size rockets of a different type carry scientific research instruments, automatic cameras, and even test animals into the upper atmosphere. Thus scientists can gather information on the density, pressure, composition, and temperature of the upper air and count the number of cosmic rays striking the Earth. Still others propel research airplanes at extreme altitudes. Burning gases are ejected forcibly and violently from an exhaust nozzle of a rocket. The opposed reaction to this exhaust blast, and not the exhaust blast itself, moves the rocket forward.