Mysterious lunar whirlpools may have been caused by volcanic activity

The researchers found new clues about the origin of the mysterious whirlpools on the surface of the moon. Moon, our closest celestial body, did not always exist in its present form. There was a volcanic and magnetic past and the researchers suggest that geological activity probably led to the formation of lunar whirlpools.

Lunar vortices are shiny and twisted patterns scattered on the dark surface of the moon. Reiner Gamma is one of the most characteristic motifs. It is about 40 miles long and has been the subject of intense scientific studies for decades.

Previous observations have revealed that lunar vortices existed at a strong magnetic field and that these bright, swirling streaks appeared to be less altered than their surroundings.

"But the cause of these magnetic fields, and therefore whirls themselves, had long been a mystery," said Sonia Tikoo, co-author of the study at Rutgers University. "To solve it, we had to find out what kind of geological feature could produce these magnetic fields – and why their magnetism was so powerful."

The researchers combined all the information on the complex geometry of the lunar vortices and the magnetic field forces associated with them and developed mathematical models. The models indicated that each lunar vortex must be placed above a narrow magnetic object just below the lunar surface. The idea is similar to that of lava tubes, underground caves created by volcanic activity. As the lava moves towards the surface, it leaves a vast network of complex and deep structures. These underground networks of lava tubes are found in many volcanic areas on Earth.

Researchers believe that volcanic eruptions have also made lunar tubes and lunar vortices so powerful. Many lunar rocks become very magnetic with a temperature of over 600 degrees Celsius in an oxygen-free environment. High temperatures can expose the material to a chemical change and release metallic iron. The iron will become magnetized in the presence of a sufficiently strong magnetic field nearby. Today, the magnetic field of the moon is not strong enough to show the same phenomenon.

"Nobody had thought of this reaction in terms of explaining these exceptionally strong magnetic characteristics on the moon," Tikoo said. "This was the last piece of the understanding puzzle of magnetism that underlies these lunar whirlpools."