"The Blue Marble" is a famous photograph of Earth taken on 7 December 1972 by the crew of the Apollo 17 spacecraft at a distance of approximately 55,000 km. It is one of the most widely distributed photographic images in existence.

Apollo 17's late-day (EST) December launch meant that the spacecraft passed over Africa during daylight hours in Africa; the mission's timing during the Southern Hemisphere's summer meant that Antarctica was also illuminated. The photograph was taken approximately five hours after the spacecraft's launch, while en route to the Moon. Apollo 17, notably, was the last manned lunar mission; no humans since have been at a range where taking a "whole-Earth" photograph such as "The Blue Marble" would be possible.

NASA officially credits the image to the entire Apollo 17 crew — Eugene Cernan, Ronald Evans and Jack Schmitt — all of whom took photographic images during the mission with an on-board Hasselblad camera. Schmitt later claimed that he personally took the famous image, but the identity of the photographer is unverifiable.

"The Blue Marble" was the first clear image of an illuminated face of Earth. Released during a surge in environmental activism during the 1970s, the image was seen by many as a depiction of Earth's frailty, vulnerability, and isolation amid the expanse of space. NASA archivist Mike Gentry has speculated that "The Blue Marble" is the most widely distributed image in human history.

Subsequent similar images of Earth (including composites at much higher resolution) have been also been termed "blue marble" images, and the phrase "blue marble" (as well as the picture itself) is used frequently by environmental activism organizations or companies attempting to promote an environmentally-conscious image. There has also been a children's television program called The Big Blue Marble .

External link

• "Visible Earth" http://visibleearth.nasa.gov/cgi-bin/viewrecord?11656 NASA "Blue Marble" imagery