The Blue Marble – Earth as seen by Apollo 17 in 1972. NASA/Apollo 17 crew; taken by either Harrison Schmitt or Ron Evans.
On December 7, 1972, the crew of Apollo 17 spacecraft took a photo of Earth from the space, at a distance about 45,000 kilometers (28,000 miles). This image, with the official NASA designation AS17-148-22727, became known as “The Blue Marble”.
In fact, it was not the first clear image of Earth taken from the space – similar photos had already been taken as early as 1967. But, the 1970s were the scene of a big surge in environmental activism. For example, on April 22, 1970, the first “Earth Day” organized by Gaylord Nelson, former senator of Wisconsin, and Denis Hayes, Harvard graduate student. Millions of people gather in the United States for the event.
So, in today’s terms, image AS17-148-22727 went “viral” and became a symbol of the environmental movement, as a depiction of Earth’s frailty, vulnerability, and isolation amid the vast expanse of space. According to the NASA archivist Mike Gentry, it is among the most widely distributed images in human history.