• Main Authors: Gregory A Neumann, John F Cavanaugh, Xiaoli Sun, Erwan M Mazarico, David E Smith, Maria T Zuber, Dandan Mao, David A Paige, Sean C Solomon, Carolyn M Ernst, Olivier S Barnouin
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: North Pole
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1072.2395; http://www-geodyn.mit.edu/zubersite/pdfs/neumannetalsci.pdf

Measurements of surface reflectance of permanently shadowed areas near Mercury's north pole reveal regions of anomalously dark and bright deposits at 1064 nm wavelength. These reflectance anomalies are concentrated on polewardfacing slopes and are spatially collocated with areas of high radar backscatter postulated to be the result of near-surface water ice. Correlation of observed reflectance with modeled temperatures indicates that the optically bright regions are consistent with surface water ice, whereas dark regions are consistent with a surface layer of complex organic material that likely overlies buried ice and provides thermal insulation. Impacts of comets or volatile-rich asteroids could have provided both the dark and bright deposits.