Undergraduate Honors Theses

Thesis Defended

Fall 2017

Document Type


Type of Thesis

Departmental Honors



First Advisor

Mihaly Horanyi


The lunar surface is exposed to many violent interactions, which include the impinging solar wind, micrometeorite bombardment and large cometary nuclei. Yet in such a destructive envi- ronment, a few beautiful and enigmatic surface features called lunar swirls have emerged in the presence of crustal lunar magnetic anomalies (LMAs) [1]. Theories attempting to explain all the anomalous properties of lunar swirls range from impinging swarms of micrometeorites [2],[3], the magnetic shielding of solar wind [4],[5] and the electrostatic transport of lofted dust grains [6]. While all three of the theories seem to satisfy some of the swirl properties, none can sufficiently explain them all [7]. For this reason, additional or complementary models may be needed to resolve all observed phenomenon. In this thesis, a new model is proposed which attempts to reconcile the solar wind standoff theory with the unique photometric properties of swirls. This model assumes that magnetized lunar dust, following a ballistic trajectory, will rotate in response to the torque they feel in the presence of an LMA, thereby producing a characteristic landing pattering in the swirl regolith. To test the hypothesis, the rotation of needle like dust grains are simulated using a simple rotation model. The emergent landing pattern is then analyzed for regions of grain uniformity. No such model has previously been explored, and the results of the simulation seem to justify further consideration, especially since grain orientation may provide a novel approach to understanding the reflectance patterns observed from lunar swirls.

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