Looking at the moon through a telescope, you may notice some wavy patterns on the surface of the rock. These patterns, often colloquially referred to as “lunar swirls”, have baffled scientists for some time.
However a recent study conducted by Rutgers University and published in the Journal of Geophysical Research has just shed light on the origins of the phenomena.
Using computer modeling, researchers were able to determine that each swirl is near or above a narrow magnetic object close to the moon’s surface. These “objects” are where lava tubes would previously have existed and are the result of long-lasting volcanic activity on the moon.
According to the research, these structures are the result of lava flows of lunar rock that left dark planes over the entire lunar surface 3 to 4 billion years ago and are behind the “lunar swirls” as well.
The presence of lava would also explain the magnetic fields present there — when lunar rock is heated to temperatures above 600 degrees Celsius in an oxygen-poor environment, it is strongly magnetised.
Magnetic fields on the moon and lunar volcanoes
According to the study, conducted by Sonia Tikoo and her colleagues at Rutgers University, there was once a central magnetic field on the moon, similar to the magnetic field on Earth.
The timelines for the lava flows and the presence of the moon’s magnetic field would have overlapped too, which adds to the body of evidence that supports the theory of magnetic lava tubes.
“No one had thought about this reaction in terms of explaining these unusually strong magnetic features on the moon,” said Tikoo in a press release. “This was the final piece in the puzzle of understanding the magnetism that underlies these lunar swirls.”