Mathematical models developed based on the intricate geometry of lunar swirls, and the strengths of the magnetic fields associated with them is consistent with lava tubes that happen to be magnetic due to a reaction that may be unique to the moon's environment at the time of those ancient eruptions, over 3 billion years ago
The mystery behind lunar swirls, one of the solar system's most striking visual anomalies, may finally be cracked by a joint Rutgers University and University of California Berkeley study. Lunar swirls look like bright, windy clouds coated on the moon's murky surface. The most well-known, termed Reiner Gamma, is around 40 miles long and popular with backyard astronomers. Most lunar swirls share their positions with powerful, localized magnetic fields.
The bright & dark patterns may result when those magnetic fields swerve particles from the solar wind and cause some parts of the lunar surface to weather more slowly. Past experiments have found that many moon rocks become extremely magnetic when heated more than 600 degrees Celsius in an oxygen-free setting. This is due to certain minerals breaking down at high temperatures and release metallic iron. If there happens to be a solid and ample magnetic field nearby, the freshly formed iron will become magnetized along the direction of that field.