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 whole-moon 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 gauss-cu cm for typical inducing fields of one ten-thousandth 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 iron-rich 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