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As detailed in a recent journal publication by the authors of this abstract, women have made significant contributions in the fluvial, aeolian, and (cryo)volcanic subdisciplines of planetary geomorphology, despite undeserved challenges to their participation. Some women—in particular, women of color—are highlighted in this work to show a part of these foundational contributions. As the latter half of the 20th century was a revolutionary time for terrestrial geomorphology and the inception of the discipline of planetary geomorphology, we focused our research into these contributions on women scientists who were working during this time. We also focused on women working in our scientific subdisciplines so that we could provide proper context for their work. These contributions have occurred both as discoveries in terrestrial geomorphology leading to follow-on discoveries in planetary geomorphology and through serving as educators and role models. With women increasingly achieving positions of influence both in the geo- and planetary sciences as in American society, this research allows us to celebrate these contributions of women and particularly women of color while looking forward to a more complete record of their past contributions and greater future achievements.

Dawn revealed that Ceres is a compelling target whose exploration pertains to many science themes. Ceres is a large ice- and organic-rich body, potentially representative of the population of objects that brought water and organics to the inner solar system, as well as a brine-rich body whose study can contribute to ocean world science. The Dawn observations have led to a renewed focus on planetary brine physics and chemistry based on the detection of many landforms built from brines or suspected to be emplaced via brine effusion. Ceres’ relative proximity to Earth and direct access to its surface of evaporites that evolved from a deep brine reservoir make this dwarf planet an appealing target for follow-up exploration. Future exploration, as described here, would address science questions pertinent to the evolution of ocean worlds and the origin of volatiles and organics in the inner solar system.

Dwarf planet Ceres is a compelling target for future exploration because it hosts at least regional brine reservoirs and potentially ongoing geological activity. As the most water-rich body in the inner solar system, it is a representative of a population of planetesimals that were likely a significant source of volatiles and organics to the inner solar system. Here we describe possible medium-class (around $1 billion) mission concepts that would determine both Ceres’ origin and its current habitability potential. Habitability is addressed through a combination of geological, geophysical, and compositional investigations by (i) searching for evidence from orbit of past and ongoing geological activity near landforms interpreted as brine-driven volcanic structures and (ii) probing the brine distribution below one of these regions with electromagnetic sounding (in situ). Two approaches were considered for compositional measurements, which address both habitability and origins: (1) in situ exploration at two sites and (2) sample return from a single site. Both concepts targeted material at Occator crater, which is one of the youngest features on Ceres (∼20 Ma) and a site rich in evaporites evolved from recently erupted brine sourced from a region >35 km deep. We conclude that a sample return architecture from these young evaporite deposits offers greater science return by enabling high-resolution analysis of organic matter (trapped in salt minerals) and isotopes of refractory elements for a similar cost and less science risk than in situ analyses. This manuscript describes the six science objectives and the two implementation concepts considered to achieve those objectives.