Why the period between 1960 and 1969 is regarded as the busiest period in space exploration history

It was known as the space race where two competing superpowers raced to the moon. The USSR had the early lead launching Sputnik and Vostok programmes including Vostok 1 on which , as of April 12, 1961, Yuri Gagarin became the first human in space. The USA took the lead with the Apollo missions and as of July 1969 Neil Armstrong became the first human on the moon. We can, being very simplistic (perhaps over simplistic), argue that the space race ended in 1969 when the political climate changed and the space race was no longer an extension of the arms race and became about purely scientific exploration. At this point a greater emphasis on international cooperation rather than competition resulted in the building of the International Space Station. Now in the early part of the 21st century a new "space race" has begun with private companies competing in various directions (asteroid mining, space tourism and even an ambitious decade long project with aspirations of putting humans on Mars).

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