No study of the Clementine mission is complete without a note about the quite different "cultures" operating within DOD and NASA. A full analysis of these differences was beyond the scope of this study. Several differences, however, were immediately obvious to COMPLEX. These include:
An issue related to the different cultures of DOD and NASA is their potential rivalry. Although the size and scope of DOD's space activities match or exceed those of NASA's, there has been little direct competition between the two programs in the past. Recent concerns about the hazards posed by near-Earth objects and the U.S. Air Force's reported interest in assuming the role of lead agency for planetary defense could exacerbate potential rivalries. With proper management, however, such a rivalry could be constructive.
The Clementine mission's primary goals were to space-qualify advanced, lightweight imaging and multispectral cameras (as well as component technologies) and to test autonomous operation for the next generation of DOD spacecraft. Shortly after the idea for this mission was conceived, secondary objectives—to perform a 2-month global mapping survey of the Moon and a flyby of the near-Earth asteroid, 1620 Geographos—were added. The specific science goals for Clementine were dictated by the capability of the spacecraft and the availability of instruments that matched this capability, rather than by well-established priorities for lunar science.4,5
To meet BMDO's goals, Clementine implemented a streamlined management style that included a rapid design and development program, with an approval-to-launch time line of 22 months. Of particular note was an innovative approach to mission operations and data handling, characterized by the intimate involvement of the science team in the day-to-day, indeed hour-to-hour, operation and planning of the science observations. The spacecraft was designed, built, tested, launched, and operated for a reported cost of about $80 million ($9 million for spacecraft systems, $8 million for instruments, $38 million for spacecraft integration, $20 million for the launch vehicle, and $5 million for operations; see Table 1.1).6
The spacecraft, whose characteristics are summarized in Box 1.1, was launched on January 25, 1994 (by a refurbished Titan IIG ICBM), and, using a phasing-orbit transfer trajectory, was inserted into a polar orbit about the Moon on February 19, 1994. It orbited the Moon for 71 days, during which it acquired almost 2 million digital images of the Moon at visible and infrared wavelengths, improved the determination of the Moon's gravitational field, and, through laser ranging, accurately measured the global lunar topography. The asteroid flyby and its accompanying test of autonomous navigation were aborted because, following a software error, the attitude control gas was entirely depleted.
The first half of the remainder of this report provides a preliminary assessment of the science accomplishments of Clementine; this assessment is based on a series of published papers7 as well as interviews with team members and other lunar researchers. The report then lists some of the lessons that the space science community might learn from Clementine's mode of operation, which had more in common with the Discovery and MidEx approach than with traditional NASA missions.