Credit: APOLLO IMAGE ARCHIVE/NASA

In December 1972, Eugene Cernan became the last man to walk on the Moon. Cernan commanded Apollo 17, the last of NASA's manned missions in the Apollo programme. Apollo 17, like Apollo 15 and 16 before it, carried the Apollo Mapping (or Metric) camera, which was used to photograph the lunar surface. The negatives of the developed film have been stored in a freezer at the Johnson Space Center in Texas ever since. Concerned for the future of the films, and the legacy of the Moon landings, the JSC, with Arizona State University and the Lunar Planetary Institute, are now creating the 'Apollo image archive' (http://apollo.sese.asu.edu), scanning the ageing film to create digital images that will be available to scientists and the public alike.

These are no ordinary scans, however. To preserve valuable information, the scanned images are produced with exceptionally high resolution, 200 pixels per millimetre, and with a 14-bit grey scale — corresponding to 16,384 shades of grey. The first five images are now available. Although before you download them, be warned that the raw-scan files run to 1.3 gigabytes...