PLANETARY CAVES – GOALS, OBJECTIVES, AND AN EXPLORATION ROADMAP FOR THE NEXT DECADE (Invited Presentation)

We are in the initial phase of exploring the subterranean voids of our Solar System. Research into planetary caves requires cross-planetary-body interdisciplinary investigations that include geology, climatology, astrobiology, robotics, and operations. To date, we have identified landscapes associated with caves, with varied cave-forming processes and evolutionary mechanisms, from Mercury to Pluto. Over 1000 potential cave openings have been identified on Mars and nearly 200 have been observed on the Moon.

Planetary caves maintain stable microclimates that potentially host volatiles, such as water ice and organic matter, and also provide access to the near-surface geologic record without a need to drill or dig. Thus, caves may preserve records of volatile delivery and climate change. These features represent a unique environment that is coupled with, but largely buffered from, surface thermal conditions, as their interiors typically reflect the average annual temperature at the surface. Additionally, caves are shelters from ionizing space radiation, high alpha-particle flux and micrometeoroid bombardment, and the stability of cave microclimates should help to preserve evidence of extinct or perhaps extant life.

Given these advances, a diverse and interdisciplinary community of planetary caves researchers and engineers has emerged. Their activities are partially documented through a series of workshops and conferences from the last 13 years. These meetings brought together scientists and engineers from around the world to discuss the scientific possibilities and engineering challenges for cave research on other bodies.

Attendees at the last planetary caves conference (18-12 February 2020) determined that a goals-and-roadmap document, like those of the Assessment and Advisory Groups, is needed to establish a common framework for planetary cave research. The five goals that were selected can be summarized as: (1) Where are the caves? (2) How did they form? (3) What controls their individual microclimates? (4) Has anything ever lived there? (5) Prepare for future human exploration. This invited presentation will review the initial conception of the proposed roadmap, which has been submitted as a white paper to the National Academy of Sciences Planetary Science and Astrobiology Decadal Survey.