Due to the tilt of the Moon's spin axis (1.54°), some regions near the poles are in permanent shadow while other nearby regions remain illuminated for the majority of the year. This subtle tilt causes lighting changes from lunation to lunation. The poles are most illuminated at their respective summer solstice. Thus images for the NAC north pole mosaic were acquired during the northern solstice (2010-01-18 through 2010-06-07), and layered in order of the greatest incidence angle and sub-solar latitude closest to the pole. The mosaic has a latitude range of 85.5° to 90° and is stored as 40 polar stereographic map tiles.
The tiles are in latitudinal bands of 1.5°, 1°, 1°, and 1° radiating from the pole. There are four tiles in the first band (88.5° to 90° latitude), eight in the second (87.5° to 88.5° latitude), twelve in the third (86.5° to 87.5° latitude), and sixteen in the fourth (85.5° to 86.5° latitude).
NAC images were map projected onto the LOLA DEM using the LOLA crossover corrected ephemeris. The images were not registered to one another.
Each file is named with the following pattern:
NAC_POLE_NORTH_P###N????
where:
P indicates the map projection (P=Polar Stereographic)
###N indicates the center latitude in 1/10th degrees North (N)
???? indicates the center longitude in 1/10th degrees East
When citing this product, use the following reference:
Wagner, R. V., Speyerer, E. J., Robinson, M. S., and LROC Team. (2015). New Mosaicked Data Products from the LROC Team. In Lunar and PlanetaryScience Conference (Vol. 46, abstract #1473).https://www.hou.usra.edu/meetings/lpsc2015/pdf/1473.pdf
For more information on LROC Reduced Data Records (RDRs), please refer to the LROC RDR Software Interface Specification (SIS).