Curiosity's Investigation of the Bagnold Dunes, Gale Crater: Overview of the Two-Phase Scientific Campaign and Introduction to the Special Collection

Between November 2015 and April 2017, Curiosity performed the first in situ investigation of an extraterrestrial dune field—the active Bagnold Dunes of Gale crater, Mars. The campaign consisted of two phases: Phase 1 occurred in southern fall/winter at Namib and High Dunes, two barchan dunes along the trailing edge of the dune field; Phase 2 occurred in southern summer at the Nathan Bridges Dune, a linear dune, and Mount Desert Island, a ripple field along the southern margin of the dune field. Both phases included a suite of observations and measurements that bear significance to our understanding of modern winds, associated sand fluxes, bedform morphology, and physical properties, composition, provenance, and sorting of eolian materials. Altogether, results described in a total of 26 manuscripts (11 of which are presented in this special collection) define the current understanding of Martian eolian processes at subdune scales, complementing previous orbiter-based studies that encompassed larger scales.