The Major-Element Composition of Mercury’s Surface from MESSENGER X-ray Spectrometry

• DOI: 10.1126/science.1211567
• Publication Date: 2011-09-29T18:45:44Z
• Authors: Larry R. Nittler; Richard D. Starr; Shoshana Z. Weider; Timothy J. McCoy; William V. Boynton; Denton S. Ebel; Carolyn M. Ernst; Larry G. Evans; John O. Goldsten; David K. Hamara; David J. Lawrence; Ralph L. McNutt; Charles E. Schlemm; Sean C. Solomon; Ann L. Sprague
• Keywords: Mercury

X-ray fluorescence spectra obtained by the MESSENGER spacecraft orbiting Mercury indicate that planet's surface differs in composition from those of other terrestrial planets. Relatively high Mg/Si and low Al/Si Ca/Si ratios rule out a lunarlike feldspar-rich crust. The sulfur abundance is at least 10 times higher than silicate portion Earth or Moon, this observation, together with Fe abundance, supports view formed highly reduced precursor materials, perhaps akin to enstatite chondrite meteorites anhydrous cometary dust particles. Low Ti abundances do not support proposal opaque oxides these elements contribute substantially Mercury's variable reflectance.