In the late 1940s, English astronomer Sir Fred Hoyle remarked, “Once a photograph of the Earth, taken from the outside, is available … a new idea as powerful as any in history will be let loose.”

NASA’s study of Earth’s climate and atmosphere has long been a central focus of its science mission. But perhaps no single piece of research has had as much impact as the simple photographs of Earth taken by NASA’s early astronauts, who fulfilled Fred Hoyle’s prediction.

You can also find this graphic on NASA’s Climate 365 Tumblr page.