Unlike Earth, the moon today has no global magnetic field generated by its core. On our planet, that field is produced by the movement of liquid iron in the outer core, a mechanism known as the geodynamo. The process works on a similar principle to a bicycle dynamo, which converts mechanical motion into electrical current.
The moon's core no longer appears to churn in the same way, but that may not always have been the case. According to a report from Phys.org, the far side of the moon is providing clues about whether the moon once had a magnetic field of its own.
Because there is only a single source, there are no conflicting accounts to compare. The significance of the finding lies in what the lunar far side could reveal about the moon's interior history and why its dynamo stopped while Earth's continues to run.