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The photography and data acquired during Apollo Mission 15's 
six days of lunar orbital photography have provided a unique 
opportunity to measure the moon in both a geodetic and topo- 
graphic sense. The information obtain ned from earthbased and 
spacecraft sensors should enable photogrammetric development of an 
improved selenodetic system to support lunar exploration and 
scientific study. 
Conventional photogrammetric intensification and extension of 
geodetic control is not applicable in this situation, as existing 
lunar surface positions are inherently inferior to positienni 
information that can be derived through the combined use of Apollo 
15 Metric Camera System and associated earthbased tracking data. 
The three laser retroreflectors established at Apollo 11, 14^ and 
15 landing sites, constitute an exception. It is sapectet that 
the continued laser observations of earth to moon distance and 
direction will significantly contribute to selenodetic system 
development. The reflector at Hadley Rille is the only station in 
the area of Apollo 15 photographic coverage. : 
Basic definition of. position 7 respect to the center of 
lunar mass is defined through the National Aeronautics and Space 
Administration's (NASA) Poi of a spacecraft orbital 
ephemeris based on integration of earthbased Doppler observations 
using the presently accepted planetary ephemeris (defining earth- 
moon positional relationship with respect to time) and lunar 
libration. and gravity models. The Apollo 15 Metric Camera System's 
recording of precise time of exposure of companion frame terrain 
and stellar photographs provide a relation to spacecraft ephemeris 
to establish exposure station position as well as the means of 
determining camera orientation with respect to celestial reference. 
In addition the laser altimeter component of the Metric System 
simultaneously records exposure station to lunar surface distance. 
Apollo 15's photographic coverage (Fig. 1) was constrained to 
the primary mission objective of landing astronauts at 26° North 
lunar latitude. Vertical stereoscopic photography comprising some 
1700 frames was obtained during 14 orbital revolutions and covers 
10 percent of the lunar surface. Also, the spacecraft was rolled 
during two orbital revolutions to extend coverage with north and 
south looking high obliques. Two revolutions of pitched low oblique 
photography, overlapping the primary coverage, was also acquired. 
While not directly involved in selenodetic system development, 
Apollo 15's panoramic camera provided excellent high resolution 
photography which has enabled identification of minute lunar 
features and intensification of point positions and elevations 
derived with the Metric System's frame photography. Table 1