Selenology Today # 7 July 2007 - Home

GEOLOGIC LUNAR RESEARCH SELENOLOGY TODAY # 7
The 2 nd and 4 th derivative plots better define the center of the absorption trough area.
2. Theophilus (Central Peak Region):
Figure 1-9a
Average of 8 Pixel Rows Plotted
The spectra of the Theophilus central peaks demonstrates no absorption trough between
900 and 1050 nm. This would be consistent with a composition of nearly pure
anorthosite with little mafic material present (Pieters and Englert, 1993). This is
consistent with reports in the literature. Recently, however, there has been a report that
the central peaks may also contain some minor deposits of olivine (Pieters and
Tompkins, 1999; Peterson et al., 1997). The slit position for Theophilus is shown in
Appendix 3.
A spline smoothed curve-fit to the Theophilus data is shown in Figure 1-9b and the 1 st
derivative curve for the data is shown in Figure 1-9c .
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