In the earlier period, launching a spacecraft by rocket was expensive and uneconomical, because the rocket could only be used once. The space shuttle breakthrough made space travel reasonably priced by inventing a spacecraft that could be used again and again, multiple times. The space shuttle is equipped with a craft called an Orbiter, which is a pair of rocket boosters and a massive fuel tank. The fuel tank cannot be reprocessed and used. The space shuttle takes off like a rocket using the boosters and fuel tank, thrusts into an orbit around the Earth, and then returns like an airplane, with the orbiter gliding into Earth on a usual landing strip.

The space shuttle can be used to launch space probes on their expeditions to far-away planets, deposit satellites on their orbits or flight path, and rescue them for repair & maintenance. It can also encompass a tiny space laboratory in its payload bay where scientists perform various experiments.

The speed required getting into an orbit or flight path around the Earth is an astonishing 17,410mph (28,080kph). To attain this enormous speed, the space shuttle’s three main engines need the assistance of two solid-fuel boosters. These five engines generate as much power as more than 140 Boeing 747 jumbo jets. At an altitude of around 30mi (45-50km), the boosters shutdown and drop back to earth, slowed down by parachutes. They drop into the ocean, to be recovered and used again.

A fuel tank attached to the bottom of the orbiter carries liquid hydrogen and liquid oxygen for the main engines to burn. After eight minutes, and a height of about 68mi (110km), the fuel tank is abandoned and burns up in the atmosphere. Less than 10 minutes after blast-off, the craft is in its orbit or flight path.