Recently published in JGR-Planets is a new joint University of California, Berkeley (Dr. Doug Hemingway) and Rutgers University (Prof. Sonia Tikoo) study that explores the origins of lunar swirls. Lunar swirls are enigmatic bright and dark patterns on the lunar surface that that resemble clouds or squiggles. The geometry of the optical anomalies associated with swirls resemble the predicted morphologies of magnetic field lines emanating from a subsurface geological source body. Indeed, most swirls are also co-located with strong localized magnetic fields within the lunar crust, suggesting that the magnetic fields play a role in producing the swirl markings, either by solar wind standoff or electromagnetic sorting of fine grains within the lunar regolith. In their paper, Hemingway and Tikoo describe how the magnetic sources of lunar swirl source bodies should ideally be narrow and shallow - a morphology consistent with magmatic dikes or buried lava tubes in the lunar subsurface.
To learn more, read the full Rutgers Today story here.