Measuring the intensity of the Moon's ancient magnetic field is an important goal of lunar sample analysis. Paleointensity estimates using thermal methods (Thellier–Thellier) raise the problem of sample alteration, especially for lunar samples carrying sulfides. To address this problem, we made real-time measurements of sample magnetization during heating with a three-axis vibrating sample magnetometer (the Triaxe, LeGoff and Gallet, 2004LeGoff M., Gallet Y. A new three-axis vibrating sample magnetometer for continuous high-temperature magnetization measurements: applications to paleo- and archeo-intensity determinations Earth Planet. Sci. Lett. 2004 ;  229 : 31-43 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti), in the hope that rapid heating would minimize alteration (Coe et al., 2014Coe R., Jarboe N., Le Goff M., Petersen N. Demise of the rapid-field-change hypothesis at Steens Mountain: the crucial role of continuous thermal demagnetization Earth Planet. Sci. Lett. 2014 ;  400 : 302-312 [cross-ref]

Cliccare qui per andare alla sezione Riferimenti). We studied the Millbillillie meteorite, which has a lunar-like mineralogy. We find that after repeated heating phases to ∼600°C, we form pyrrhotite, magnetite, and magnetic phases with low (200–270°C) Curie temperatures. These low-temperature phases appear after pyrrhotite has apparently been destroyed by subsequent heating phases, and their mineralogy is unknown. These results have implications for the paleomagnetic study of any extraterrestrial samples with even small amounts of sulfides, and further experiments are required to understand them.