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Robert V. Wagner

Publications and source records attributed to Robert V. Wagner.

3 recordsLinked to original sources

Planetary caves: A Solar System view of processes and products

We provide the first solar system wide compendium of speleogenic processes and products. An examination of 15 solar system bodies revealed that six cave-forming processes occur beyond Earth including volcanic (cryo and magmatic), fracturing (tectonic and impact melt), dissolution, sublimation, suffusion, and landslides. Although no caves (i.e., confirmed entrances with associated linear passages) have been confirmed, 3,545 SAPs (subsurface access points) have been identified on 11 planetary bodies and the potential for speleogenic processes (and thus SAPs) was observed on an additional four planetary bodies. The bulk of our knowledge on extraterrestrial SAPs is based upon global databases for the Moon and Mars, which are bodies for which high-resolution imagery and other data are available. To further characterize most of the features beyond the Moon and Mars, acquisition (preferably global coverage) and subsequent analysis of high-resolution imagery will be required. The next few decades hold considerable promise for identifying and potentially characterizing caves across the solar system.

JGR Planets

Fundamental science and engineering questions in planetary cave exploration

Nearly half a century ago, two papers postulated the likelihood of lunar lava tube caves using mathematical models. Today, armed with an array of orbiting and fly-by satellites and survey instrumentation, we have now acquired cave data across our solar system—including the identification of potential cave entrances on the Moon, Mars, and at least six other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we leveraged the expertise of an interdisciplinary group to identify a strategy to explore caves beyond Earth. Focusing primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration, our goal was to produce a framework to guide this subdiscipline through at least the next decade. To do this, we first assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave—principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and martian subsurface.

JGR Planets

A roadmap for planetary caves science and exploration

While researchers have pondered the possibility of extraterrestrial caves for more than 50 years, we have now entered the incipient phase of planetary caves exploration. Our knowledge of planetary caves varies from body to body. Earth represents the most advanced level of exploration, but many unanswered questions remain. Beyond Earth, identification of possible caves is most advanced for the Moon and Mars , with hundreds of documented candidate cave entrances and several proposed cave mission concepts. To date, the community has catalogued 2,660 SAPs on eight planetary bodies (excluding Earth) across our Solar System. Planetary caves science has the potential to significantly expand over the next decade. A potential roadmap for planetary cave research and exploration is discussed.

Nature Astronomy