Landing back on Earth from orbit or further a field has always had one major problem -how to dissipate the energy generated when slowing to a standstill from travelling at speeds of around 18,000 miles per hour (24.000 feet per second). Any solution trades velocity, friction and heat in the Earth's atmosphere. Before the space race and the advent of ballistic capsules for Mercury, Gemini and Apollo, however, a wholly different approach was evolving to return from Earth orbit. The money was on a piloted and controlled decent, capable of a pinpoint touch down.
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