Before the Space Shuttle, all space-going vehicles were built for one-time use only. ThatÕs because it was very difficult for <a href="glossary">aeronautic</a> engineers to design a spacecraft that would have the <a href="glossary">thrust</a> power to leave the EarthÕs atmosphere but still be able to survive the stress of re-entry without burning up or breaking into pieces.
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The Orbiter was the first spacecraft to overcome this problem. It is propelled into space by powerful <a href="text">rocket engines</a>. When it enters back into the EarthÕs atmosphere, its special <a href="text">aerodynamic</a> design allows it to fly through the air like a plane and come in for a soft landing on the ground.