Apollo 8 Mission
The primary purpose of the Apollo 8 mission was to further progress toward the goal of landing humans on the Moon by gaining operational experience and testing the Apollo systems. However, a great effort was also made to accomplish worthwhile scientific tasks with photography and visual observations by the astronauts. It was obvious that one of the prime tasks should be photography of the lunar surface. During the mission, a major portion of the lunar farside was in sunlight. Although almost all the farside of the Moon had been photographed by Lunar Orbiter, the spacecraft was generally rather far from the Moon, limiting it to an average resolution of about 100 meters. Apollo 8 photographs of the farside would have a much better resolution than existing pictures.
Cameras and Accessories
The onboard cameras for the Apollo 8 mission were modified Hasselblad 500 EL cameras, with 80-millimeter and 250-millimeter Zeiss panacolor lenses. For certain photographs of the lunar surface, a 60-millimeter lens with a reseau was used. Use of this lens and reseau is apparent in the views that show crosslike fiducial marks. For analytical purposes, black-and-white emulsions were determined to provide a higher degree of resolution and image clarity than the color emulsions; therefore, much of the photography is black-and-white.
The Apollo 8 photography complements the extensive coverage of Lunar Orbiter. Lunar Orbiter provided excellent high-resolution coverage of the nearside of the Moon and Apollo 8 provided excellent coverage of selected areas of the farside. Many of the photographs derived from Apollo 8 were valuable for updating existing maps and charts of the lunar farside. The photographic equipment and materials carried by Apollo 8 were designed specifically to achieve the principal photographic objectives, which were to obtain (1) vertical and oblique overlapping, or stereo strip, photographs during at least two revolutions, (2) photographs of specified targets of opportunity, and (3) photographs of a potential landing site through the spacecraft sextant.
Lunar surface coverage of Apollo 8 photography
Much of this area was photographed by Luna III and the Lunar Orbiter spacecraft. However, the Apollo 8 photography was taken with different lighting conditions and at different viewing angles.
Photography of the Earth
This striking view from the Apollo 8 spacecraft shows nearly the entire western hemisphere, from the mouth of the St. Lawrence to the southern tip of South America. Central America is clearly outlined. South America, except the high Andes Mountain chain along the west coast, is almost completely covered by clouds.
Photography of the Moon
Most of the targets of opportunity were photographed in the first few revolutions. Among the more outstanding images are the near-full-Moon views of the eastern hemisphere. This frame is centered near Mare Symthii and shows that this mare is circular rather than irregular as had been thought previously.
A Possible Landing Site
The targets of opportunity were selected to provide either detailed coverage of specific features or broad coverage of areas not adequately covered by Lunar Orbiter. The proposed landing sites were prime targets of opportunity. This image is of Approved Candidate Landing Site 1. The landing was designated for the area near the center.
Crater Giordano Bruno
Crater Giordano Bruno is shown in this image. The impact that formed the 20-kilometer-diameter crater was observed by five men on the evening of June 18, 1178, and was reported in medieval chronicles. No other similar events on the Earth or Moon have been observed during recorded history (Hartung, 1976).
Stereoscopic Strip Photography
The objective of stereo strip photography was to obtain two strips of stereoscopic photography from the farside terminator to about 60° from the nearside terminator. By taking an exposure every 20 seconds, each overlaps the previous one by approximately 60%. By combining the vertical strip with a second convergent strip, the geometry of the stereo view could be made stronger; hence, the ability to measure height differences would be better by a factor of 2.
An Excellent Stereo Pair
These photographs were taken at high Sun illumination and show various geologic features such as mass-wasting debris on crater walls and numerous small, bright craters and topographic features that are barely visible monoscopically.
Approximately 90% of the photographic objectives of the mission were accomplished. Approximately 60% of the additional lunar photographs requested as targets of opportunity were also taken despite early curtailment of crew photographic activities. Many smaller lunar features, previously undiscovered, were photographed. These features are located principally on the farside of the Moon in areas that had been photographed only at much greater distances by automated spacecraft. During the mission, seven 70-millimeter film magazines were exposed and yielded more than 150 photographs of the Earth and more than 700 photographs of the Moon. Five 16-millimeter color magazines were also exposed.Apollo Image Atlas