This one-month WAC global mosaic was created by mosaicking 1290 nadir-pointing WAC images acquired on orbits 21603 through 21778 (31 March 2014 through 15 April 2014) into a single global 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 -29.2° to -44.0°. Some gores may be present due to spacecraft slews for observations by other instruments. This mosaic uses the 643 nm band of the WAC. It uses a simple cylindrical map projection from 0°E to 360°E longitude and 90°S to 90°N latitude.
Note: From orbit 21217 through orbit 21602, the WAC was in safe mode while the instrument team investigated an electrical anomaly, so no images were acquired during that period apart from two test images on orbit 21313.
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 21643-21738).
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), off-nadir slew angle < 5°, and orbit between 21603 and 21778, inclusive. A complete image list can be downloaded under "Supplementary Downloads".
The naming scheme for this product is WAC_ORBITS_XXXXX_YYYYY, where XXXXX is the first orbit number from which images were used, and YYYYY is the last orbit.
For more information on LROC Reduced Data Records (RDRs), please refer to the LROC RDR Software Interface Specification (SIS).
When citing this product, use the following reference:
Wagner, R. V., Speyerer, E. J., Robinson, M. S., & LROC Team. (2015). New Mosaicked Data Products from the LROC Team. In Lunar and Planetary Science Conference (Vol. 46, abstract #1473). https://www.hou.usra.edu/meetings/lpsc2015/pdf/1473.pdf