Page 14 - Curriculum Visions Dynamic Book

The most famous workhorse of space today, the SpAce SHuttle (more accurately, the Space Transportation System, or STS), represents a new step forward in space science and technology—a reusable space vehicle that can also fly in the Earth’s AtmospHere.
The components
The Space Shuttle is made up of three parts. The most familiar part, which is planelike, is called the orbiter (see pages 20–29). To most people it is also known as the Shuttle.
The orbiter can land on its own and has powerful engines, but even so, it needs rocket boosting to help it take off. If it had engines powerful enough to lift it without any assistance, it would have to carry bigger and heavier motors around when they were not needed.
Takeoff, therefore, is achieved only in part by using the orbiter’s three main engines. The additional assistance
is provided by two auxiliary solid fuel boosters,
which are strapped on for the launch (see
pages 18–20). They are not connected to the
orbiter’s engines and operate only during
the first 2 minutes of the flight.
Similarly, if the orbiter carried all the fuel it needed on board, it would have to be much bulkier, and for the majority of the mission these tanks would be almost
empty. So the orbiter has a small internal tank. To allow the engines to develop enough tHrust long enough to
get the orbiter into space, a large temporary
external tank (see page 18) is strapped to its underside and connected to the orbiter engines. It provides the bulk of the liquid oxygen and liquid hydrogen fuel needed during the early stages of takeoff.
 This diagram shows the three main components of the Space Shuttle System.
External tank
Auxiliary solid rocket fuel boosters sit
on each side of the external tank.
Orbiter
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