Due to the effects of erosion, sedimentation and plate tectonics, direct evidence for the impact flux in the Earth-Moon system during the first ~2600 million years (Ma) have been erased from the terrestrial geologic record (Vredefort, South Africa, is currently the oldest known terrestrial impact structure, 2.02 Ga old). In contrast, the Moon is a tectonically stable planetary body that lacks an atmosphere. It has preserved an extensive record of its early evolution in the form of abundant impact craters and extended ejecta blankets. These extended ejecta blankets cover most of the lunar surface, i.e. the portion of the Moon accessible by samples and mission data. Current lunar studies on chronology and geologic evolution are based on data collected over the last 50 years including the Apollo and Luna sampling missions and Orbiter I-V images. In the early 90’s , a new era began with NASA’s Galileo mission, which allows us to view the Moon as a more complex body than that captured by the samples and the images of previous decades. Since Galileo, six more ESA, JAXA, ISRO, Chinese Space Agency and NASA missions have provided much greater detail and information for the understanding of the chemical and stratigraphic details of the lunar surface through the use of different spectral data (e.g. optical cameras, UV, IR, radar, laser-altimetry. The increase in lunar missions has been matched by a dramatic increase in the lunar sample base through discovery of 72 meteorites of lunar origin, providing a diverse and possibly more representative sample set of lunar rock types. In parallel with this has been the development and use of high-precision and high-resolution isotopic analytical methods (e.g. Ar-Ar, Hf-W, Re-Os, Sm-Nd, U-Pb) on lunar samples. These data have provided a new perspective on the timing and timescale of the Moon's geological evolution. As a result of these developments, lunar science is reaching a new stage of understanding that informs and guide the scientific aims of future missions (manned and unmanned) to the Moon by different Space Agencies. In particular this includes the choice of a landing site that will enable retrieval of information to unresolved key issues such as the impact flux onto the Earth-Moon system, as well as the selection of instrumentation for in-situ measurements, and samples acquisition for work in laboratories around the world.

The proposed Team for the ISSI project includes lunar specialists representing different aspects of research from remote sensing to laboratory analysis, and its aim is to discuss and write manuscripts that will bring together new and old views of lunar chronology, stratigraphy, crater formation and also volcanism. Only the International Teams in Space Science initiative enabled by the ISSI will permit such a team to come together and focus on the next stage of lunar science. Each Team-Member has new results in the framework of own nationally-funded research projects, and presently there is the need to integrate these data and produce an improved and likely more realistic “New view of the Moon”.