This one-month WAC global mosaic was created by mosaicking 4994 nadir-pointing WAC images acquired on orbits 14903 through 15318 (25 September 2012 through 30 October 2012) into a single image with seamless lighting. The orbit tracks progress across the Moon from 360°E to 0°E over the course of the month of imaging, with beta angles (the angle between the orbital plane and a vector to the Sun) going from 7.5° to 42.3°. Some gores are present due to spacecraft slews for observations by other instruments. This mosaic uses the 643 nm band of the WAC.
Each image was projected onto the GLD100 (WAC derived 100m/pixel DTM), with accurate positioning of each WAC image ensured using ephemeris provided by the LOLA and GRAIL team and an improved camera geometry model (Speyerer et al. 2014, Pre-flight and On-orbit Geometric Calibration of the Lunar Reconnaissance Orbiter Camera). All images were corrected to a common photometric geometry using a Hapke model (Sato et al. 2014, Resolved Hapke parameter maps of the Moon). To minimize lighting discontinuities near the poles, the images were mosaicked on a per-pixel basis based on incidence angle (angle between the Sun and the zenith): for each pixel in the output, the data was selected from the image with the lowest incidence angle at that location.
A note on timing: To get complete coverage at the poles, the source image list extends slightly beyond the nominal ~28 days for the orbit track to cover the entire Moon. At the equator, the first and last images with visible data will be about 40 orbits (~3 days) after or before the listed start and end times, respectively (roughly orbits 14943-15278).
Image selection details: Color and monochrome WAC images with data_quality_id < 16, exposure time <= 0.1 seconds, incidence angle < 95° (or image center within 5° of a pole), and off-nadir slew angle < 5°.