The committee evaluated only the scientific merit of each science concept in order to rank the concepts. It should be noted that all concepts discussed are viewed to be scientifically important. The science concepts are prioritized below and discussed in more detail in Chapter 3.
The bombardment history of the inner solar system is uniquely revealed on the Moon.
The structure and composition of the lunar interior provide fundamental information on the evolution of a differentiated planetary body.
Key planetary processes are manifested in the diversity of lunar crustal rocks.
The lunar poles are special environments that may bear witness to the volatile flux over the latter part of solar system history.
Lunar volcanism provides a window into the thermal and compositional evolution of the Moon.
The Moon is an accessible laboratory for studying the impact process on planetary scales.
The Moon is a natural laboratory for regolith processes and weathering on anhydrous airless bodies.
Processes involved with the atmosphere and dust environment of the Moon are accessible for scientific study while the environment remains in a pristine state.
Within the 8 science concepts above, the committee identified 35 specific science goals that can be addressed, at least in part, during the early phases of the VSE. For these science goals, the committee evaluated science merit as well as the degree to which they can be achieved within current or near-term technical readiness and practical accessibility. Within their respective science concepts, the science goals are listed in the order of their overall priority ranking (a through e) in Table 3.1 in Chapter 3.
All 35 specific science goals were also evaluated and ranked as a group, separately from the science concepts with which they are associated. The highest-ranking lunar science goals are listed in Table 5.1 in Chapter 5 in priority order. For this group of goals the committee identifies possible means of implementation to achieve each goal.
Principal Finding: Lunar activities apply to broad scientific and exploration concerns.
Lunar science as described in this report has much broader implications than simply studying the Moon. For example, a better determination of the lunar impact flux during early solar system history would have profound implications for comprehending the evolution of the solar system, early Earth, and the origin and early evolution of life. A better understanding of the lunar interior would bear on models of planetary formation in general and on the origin of the Earth-Moon system in particular. And exploring the possibly ice-rich lunar poles could reveal important information about the history and distribution of solar system volatiles. Furthermore, although some of the committee’s objectives are focused on lunar-specific questions, one of the basic principles of comparative planetology is that each world studied enables researchers to better understand other worlds, including our own. Improving our understanding of such processes as cratering and volcanism on the Moon will provide valuable points of comparison for these processes on the other terrestrial planets.
Finding 1: Enabling activities are critical in the near term.
A deluge of spectacular new data about the Moon will come from four sophisticated orbital missions to be launched between 2007 and 2008: SELENE (Japan), Chang’e (China), Chandrayaan-1 (India), and the Lunar Reconnaissance Orbiter (United States). Scientific results from these missions, integrated with new analyses of existing data and samples, will provide the enabling framework for implementing the VSE’s lunar activities. However, NASA and the scientific community are currently underequipped to harvest these data and produce meaningful