Article of the Week - The Blue Marble (Quiz starts at 7:30pm)

The Blue Marble
A famous photograph of the Earth as
taken from Apollo 17th in 1972

The Blue Marble is a famous photograph of the Earth taken on December 7, 1972, by the crew of the Apollo 17 spacecraft at a distance of about 45,000 kilometres (28,000 mi).

The name also has been applied by NASA to a modern series of image data sets covering the entire globe at relatively high resolution, created by carefully sifting through satellite captured sequences taken over time, to eliminate as much cloud cover as possible from the collated set of images.

The snapshot — taken by astronauts on December 7, 1972, at 5:39 a.m. EST (10:39 UTC) — is likely one of the most widely distributed photographic images in existence. The image is one of the few to show a fully illuminated Earth, as the astronauts had the Sun behind them when they took the image. To the astronauts, Earth had the appearance of a glass marble (hence the name).

The photograph was taken about 5 hours and 6 minutes after launch of the Apollo 17 mission, and about 1 hour 54 minutes after the spacecraft left parking orbit around the Earth to begin its trajectory to the Moon. The time of Apollo 17's launch, 12:33 a.m. EST, meant that Africa was in daylight during the early hours of the spacecraft's flight. With the December solstice approaching, Antarctica also was illuminated.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "The Blue Marble"