Talk to any Astronaut about their most revered memory from Space and the answer will inevitably be - seeing the Earth. The most vivid description was given by Neil Armstrong, the first man to walk on the moon, who said 'It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small.'