The theory was based on the fact that scientists had found clear signs of magnetization in rocks from the moon.
Based on this, the researchers concluded that the moon must have had a so-called geodynamo, ie liquid electrically conductive substances deep inside the globe which, just like an electromagnet, could maintain a permanent magnetic field.
From new analyzes shows, however, that the researchers of the time were wrong. Now we know that the moon’s core is probably too small and compact for a geodynamo, and that there is a much more probable explanation for the magnetic tracks in the moonstones:
By subjecting non-magnetic moonstones to magnetism, the rocks became magnetic, and if the moon once had a magnetic field, the tested rocks would already be magnetic when they were collected.