Magnetic studies of meteorites.

The intensity of natural remanent magnetization (NRM) is nearly proportional to the intensity of saturation remanent magnetization in achondrites and carbonaceous chondrites. The NRM in these meteorites is stable against alternating field demagnetization. The authors consider this NRM to reflect magnetic fields that were present in the early solar system. The correlation between the NRM intensity and the intensity of saturation remanent magnetization in ordinary chondrites is weak. Since the coercive force of kamacite in ordinary chondrites is very small, it is possible that the extraterrestrial remanence in many ordinary chondrites is dominated by a soft, spurious remanence. Theoretically, interplanetary magnetic fields of appropriate strength could have existed for 10 Myr in the early solar system, causing meteorites to be magnetized during the accretion and cooling stages.