October 4, 1957 – The Soviet Union launches Sputnik, Earth’s first artificial satelite, marking the start of what would become known as The Space Race.

Unfortunately I think many people misunderstood what kind of race this was – they thought it would be a sprint and by the end of the century there would people living on the Moon and Mars. Turned out it was actually a marathon. But in centuries to come perhaps people will look back at Earth from across space and remember this was the first step.