The Lunar Reconnaissance Orbiter Camera (LROC) images the Moon with two Narrow Angle Cameras (NAC) and one Wide Angle Camera (WAC). The NACs acquire monochrome images with pixel scales ranging from 25-cm to 400-cm while the WAC is a multispectral imager (321-689 nm) with pixel scales of 100-m to 400-m in the visible bands and 400-m to 1600-m with the two ultraviolet bands. Since July of 2009 over 675,000 NAC images of the illuminated surface of the Moon were acquired; in total about 70% of the surface is now imaged. Each month the WAC images the entire illuminated Moon in 7-wavelengths with unique lighting. Currently there are now forty global WAC image sets, the first ever multiphase-angle multispectral dataset for the Moon.
Both the WAC and NAC image sets are fundamentally changing our view of the Moon in critically important fields.
Thus far WAC imaging enabled production of the highest resolution (100-m sampling) near-global (80°S to 80°N, 0° to 360°E) topographic dataset of the Moon, titanium abundance estimates (1-km scale), resolved Hapke photometric parameter maps (30-km scale), normalized reflectance (100-m scale), UV-Visible color ratios (400-m scale), and a global morphology basemap (100-m scale).
Key LROC exploration and science results include: 1) The Moon is in a state of global contraction due to interior cooling and extensional stresses can still locally exceed the global field, with far-reaching implications for models of lunar origin and thermal evolution. 2) Impact melt is more common and voluminous than expected indicating our knowledge of energy transfer in impact events is incomplete. 3) Silicic volcanism is more common and widespread than previously known. 4) Sublunarean voids (likely formed as lava tubes) do exist on the Moon. 5) Three nearby hills on the rim of Shackleton crater are collectively illuminated for 92.1% of the year with the longest eclipse period lasting only 43 h. 6) For highland materials the opposition effect is controlled 40% by coherent backscatter in the UV, increasing to over 60% in the visible wavelengths 7) Revised basin stratigraphy calls into question the idea that Apollo 17 impact melts are samples of the Serenitatis basin-forming impact thus raising a fascinating conundrum. a) There is no evidence for a period of late heavy bombardment or b) up to half of the basin and large crater population of the Moon was created within a 30 Ma interval around 3.8 Ga in a global impact “extreme-cataclysm.” Either interpretation significantly changes our view of the impact process and history of the Earth-Moon system. 8) Discovery of >60 instances of small young volcanic features, forcing a re-examination of models of global heat flow over time. 9) Meter-scale blockiness and layering in domes and cones in the Marius Hills region reflect their construction from individual basaltic lava flows, many of which originate from C-shaped spatter-style cones. 10) NAC Re-imaging is revealing craters formed during the LRO mission allowing for precise estimates of current impact rates for bolides >10 cm diameter.