How magnetic is the moon? A new study cracks the long-standing mystery | Space
How magnetic is the moon? Analysis of rock samples from the Apollo missions suggested that the Moon had an extremely strong magnetic field early in its history – even stronger than Earth’s.
But no one could understand how such a small planetary body could have such a powerful field. Now a new study has unraveled the mystery.
Claire Nichols and her team at the University of Oxford analyzed the titanium content of lunar rocks. They found that those with high titanium content were associated with the fusion of titanium-rich materials deep within the moon, which generated a powerful magnetic field.
Coincidentally, the Apollo missions collected more samples of rocks with high titanium content, because this type of rock is more prolific in the relatively flat area where they chose to land.
The results, reported in Nature Geoscience, reveal that this sampling bias gave the misleading impression that the Moon had an extremely strong magnetic field early in its history.
Nichols and his colleagues believe that episodes of strong magnetic fields were very rare – lasting no more than a few thousand years – and that for most of the Moon’s history the magnetic field was very weak. Future Artemis missions will allow scientists to test this theory.
