2. Blue Marble

The Apollo 17 crew were the last astronauts to walk on the Moon. But they also made history when they snapped this iconic photo of the Earth dubbed “Blue Marble.” They did so in the early 1970s, when many people began to care about the planet. The serene shot showed that the third rock from the sun was worth saving – and it still is. As such, the image has long been considered one of the most iconic in the history of photo-taking.