Space Invaders

When we think of the first earth orbit, Yuri Gagarin springs to mind. And the first landing on the moon calls up images of Neil Armstrong and Buzz Aldrin in their spacesuits. What we tend to overlook is that Gagarin was preceded by Sputnik-1, and the Apollo 11 moonwalkers came after Luna-2. Manned missions, for obvious reasons, have always come after robotic probes, and will continue to do so. Machines were the first to orbit another planet, the first to land on Mars and Venus, the first to touch an asteroid, the first to send us close-up images of Saturn's rings. The list of robotic space achievements is long and impressive. In reality, the history of space exploration is overwhelmingly a history not of human missions, but unmanned ones.