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What Are the Functions of the Parts of a Space Shuttle?

In the late 1970s, NASA invented the space shuttle, the word's first reusable spacecraft. While previous spacecrafts could be used only once, the main body of the space shuttle is designed to fly at least 100 missions. The space shuttle is also the first spacecraft capable of transporting a satellite from Earth to orbit, then back to Earth.

Space Shuttle Parts
- A space shuttle has four main parts: an orbiter, an external fuel tank and two solid rocket boosters. The orbiter is where the crew rides and lives during the mission. The external fuel tank holds additional fuel to help the shuttle launch, but burns up in the atmosphere after the launch. The solid rocket boosters provide additional power for takeoff. All these parts are reusable except the external fuel tank. The solid rocket boosters provide power to get past Earth's atmosphere, but when the rocket reaches an altitude of approximately 28 miles, they fall into the ocean. They can be retrieved and reused for later flights. The orbiter continues its flight using internal engines for power.
Orbiter
- The orbiter leaves behind the solid rocket boosters and the external fuel tank before it begins to orbit Earth.
  
  The orbiter, the part of the space shuttle that travels into space, has a shape similar to an airplane. It functions like a spaceship in space and lands like an airplane when it returns to Earth, gliding at an angle to land in water. To navigate into its planned orbit in space, it uses orbital maneuvering system (OMS) engines. It also has reaction control system (RCS) engines for navigating in Earth's upper atmosphere. Once the orbiter re-enters Earth's atmosphere, the split rudder in the orbiter's tail acts as a rudder to help with navigation and also as a break to reduce speed for landing.
Launch and Orbit
- A space shuttle's mission consists of launching, achieving an orbit and accomplishing its task, re-entering Earth's atmosphere and landing. The solid rocket boosters and the external fuel tank are used only during the launch. According to Sten Odenwald, a NASA astronomer, to escape Earth's atmosphere, the space shuttle must reach speeds higher than 28,000 mph. When the shuttle has enough speed and power to go into orbit around Earth, the solid rocket boosters fall back to Earth. During its mission, the shuttle uses the OMS engines to get into orbit, stay on course and rendezvous with other space shuttles or stations if necessary.
Re-entry and Landing
- A space shuttle lands on a runway like an airplane.
  
  When the mission is accomplished, the orbiter re-enters the atmosphere at approximately a 30 degree angle and glides back toward Earth. Heat-resistant tiles on the bottom of the orbiter help protect it from re-entry friction. In the upper atmosphere, the shuttle uses its RCS engines to follow a winding path, which help reduce its speed. As it descends, the thicker atmosphere enables the airplane controls function. It lands on a runway like an airplane and uses wheel brakes, speed brakes and a drag chute to slow down and eventually stop.

Astronomy