GY676A

"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." -Neil Armstrong Here on our little wet rock in our Solar System, we often remind ourselves what a small world Earth actually is. The farther out in space we reach, the more this appears to be true. Image credit: NASA / Apollo 11, taken by Command module pilot Michael Collins. The Earth is the largest of the four inner, rocky planets in our Solar System, at more than 12,000 km in…