| タイトル | Lunar Ion Transport Near Magnetic Anomalies: Possible Implications for Swirl Formation |
| 本文（外部サイト） | http://hdl.handle.net/2060/20110007825 |
| 著者（英） | Farrell, W. M.; Killen, R. M.; Stubbs, T. J.; Halekas, J. S.; Keller, J. W. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2011-03-07 |
| 言語 | eng |
| 内容記述 | The bright swirling features on the lunar surface in areas around the Moon but most prominently at Reiner Gamma, have intrigued scientists for many years. After Apollo and later Lunar Prospector (LP} mapped the Lunar magnetic fields from orbit, it was observed that these features are generally associated with crustal magnetic anomalies. This led researchers to propose a number of explanations for the swirls that invoke these fields. Prominent among these include magnetic shielding in the form of a mini-magnetosphere which impedes space weathering by the solar wind, magnetically controlled dust transport, and cometary or asteroidal impacts that would result in shock magnetization with concomitant formation ofthe swirls. In this presentation, we will consider another possibility, that the ambient magnetic and electric fields can transport and channel secondary ions produced by micrometeorite or solar wind ion impacts. In this scenario, ions that are created in these impacts are under the influence of these fields and can drift for significant distances before encountering the magnetic anomalies when their trajectories are disrupted and concentrated onto nearby areas. These ions may then be responsible for chemical alteration of the surface leading either to a brightening effect or a disruption of space weathering processes. To test this hypothesis we have run ion trajectory simulations that show ions from regions about the magnetic anomalies can be channeled into very small areas near the anomalies and although questions remain as to nature of the mechanisms that could lead to brightening of the surface it appears that the channeling effect is consistent with the existence of the swirls. |
| NASA分類 | Lunar and Planetary Science and Exploration |
| 権利 | Copyright, Distribution as joint owner in the copyright |
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