Iron abundance and magnetic permeability of the moon.
Abstract
A larger set of simultaneous data from the Apollo 12 lunar surface magnetometer and the Explorer 35 Ames magnetometer are used to construct a wholemoon hysteresis curve, from which a new value of global lunar permeability is determined to be mu = 1.012 + or  0.006. The corresponding global induced dipole moment is 2.1 times ten to the eighteenth power gausscu cm for typical inducing fields of one tenthousandth gauss in the lunar environment. From the permeability measurement, lunar free iron abundance is determined to be 2.5 + or  2.0 wt %. Total iron abundance (sum of iron in the ferromagnetic and paramagnetic states) is calculated for two assumed compositional models of the lunar interior: a free iron/orthopyroxene lunar composition and a free iron/olivine composition. The overall lunar total iron abundance is determined to be 9.0 + or  4.7 wt %. Other lunar models with a small iron core and with a shallow ironrich layer are discussed in light of the measured global permeability. Effects on permeability and iron content calculations due to a possible lunar ionosphere are also considered.
 Publication:

Lunar and Planetary Science Conference Proceedings
 Pub Date:
 1974
 Bibcode:
 1974LPSC....5.2761P
 Keywords:

 Iron;
 Lunar Composition;
 Lunar Magnetic Fields;
 Magnetic Permeability;
 Abundance;
 Apollo 12 Flight;
 Astronomical Models;
 Explorer 35 Satellite;
 Lunar and Planetary Exploration