Much like our blue planet, the moon was once home to a magnetic core. In fact, the Moon’s magnetic field may have been greater than Earth’s, scientists believe, after reviewing samples retrieved with the help of Apollo astronauts. While our planet’s magnetic field has a strength of 50 microteslas, the moon’s magnetic field may have been as strong as 70 microteslas.
There are still many mysteries that need to be unveiled, for one, how and when did our satellite’s magnetic field end? Although the moon no longer has a global magnetic field, as it once did, moon rocks still contain traces that may provide valuable information. Until now, scientists are still uncertain whether the moon’s magnetic field would have been generated the same way as Earth’s field does.
One theory that scientists came up with is that cosmic impacts may have caused sparks in the moon’s plasma, generating strong but short magnetic fields. This would be one plausible explanation for the magnetized rocks that Apollo astronauts found.
On the other hand, Sonia Tikoo and Benjamin Weiss, whose study has been published in the journal Science, suggest that the moon’s magnetic field could have been the result of a molten liquid core that our natural satellite possessed.
“We know the Moon had a powerful magnetic field between 4.25 and 3.56 billion years ago, which was much stronger than the Earth’s magnetic field today.”
Weiss said.
During the past half-a-dozen years, scientists have repeatedly conducted computer simulations to see whether the moon could have possessed a magnetic core. Earth’s magnetic field, experts say, is generated by electrical-conducting fluids located inside our planet’s liquid outer core being rotated and undergoing a convection process. Scientists dubbed this “geodynamo” as our planet virtually becomes a giant dipole magnet.
“We think planets generate magnetic fields by moving electrically conducting fluids inside them.”
Weiss added.
Weiss explains that scientists have been trying to answer an essential question connected to the moon: is this body a primordial, unmelted, celestial body, such as asteroids, or is it a melted evolved body possessing a multilayered structure?
If and when scientists discover the answer to this question, they will finally be able to understand the origin of the moon. While some models suggest that it started off as a cold body, others insist that it was created as a result of a massive impact and that at that time, it must have been hot, Weiss told reporters.