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Planetary dunes tell of otherworldly winds

Dune fields are common on beaches and in deserts—think of the imposing sand hills and sinuous ripples of the Sahara in Africa or the Karakum in Central Asia, for example—as well as underwater on the beds of rivers, lakes, and oceans. The varied shapes, sizes, and orientations of both modern dunes and those preserved in the geologic record tell of the conditions under which they formed, particularl
Authors
Timothy N. Titus, S. Diniega, L.K. Fenton, Lynn D.V. Neakrase, James R. Zimbelman

How well do we know Europa’s topography? An evaluation of the variability in digital terrain models of Europa.

Jupiter’s moon Europa harbors one of the most likely environments for extant extraterrestrial life. Determining whether Europa is truly habitable requires understanding the structure and thickness of its ice shell, including the existence of perched water or brines. Stereo-derived topography from images acquired by NASA Galileo’s Solid State Imager (SSI) of Europa are often used as a constraint on
Authors
Michael T. Bland, Randolph L. Kirk, Donna M. Galuszka, David Mayer, R. A. Beyer, Robin L. Fergason

Clustering supported classification of ChemCam data from Gale crater, Mars

The Chemistry and Camera (ChemCam) instrument on board the MSL rover Curiosity has collected a very large and unique dataset of in-situ spectra and images of Mars since landing in August 2012. More than 800,000 single shot LIBS (laser-induced breakdown spectroscopy) spectra measured on more than 2,500 individual targets were returned so far by ChemCam. Such a dataset is ideally suited for the appl
Authors
K. Rammelkamp, Olivier Gasnault, Olivier Forni, Candice C. Bedford, Erwin Dehouck, Agnès Cousin, Jeremie Lasue, Gaël David, Travis S. J. Gabriel, Sylvestre Maurice, Roger C. Wiens

Appendix E: Mars nomenclature

This appendix provides an overview of the history and current standards for Mars geographic nomenclature. The article describes the International Astronomical Union's approval process for planetary nomenclature, and discusses the role of USGS Astrogeology in managing the Gazetteer of Planetary Nomenclature website and background database and
Authors
Tenielle A. Gaither

Improving the usability of Galileo and Voyager images of Jupiter’s moon, Europa

NASA's Voyager 1, Voyager 2, and Galileo spacecraft acquired hundreds of images of Jupiter's moon Europa. These images provide the only moderate- to high-resolution views of the moon's surface and are therefore a critical resource for scientific analysis and future mission planning. Unfortunately, uncertain knowledge of the spacecraft's position and pointing during image acquisition resulted in si
Authors
Michael T. Bland, Lynn A. Weller, Brent Archinal, Ethan Smith, Benjamin H Wheeler

Active neutron interrogation experiments and simulation verification using the SIngle-scintillator Neutron and Gamma-Ray spectrometer (SINGR) for geosciences

We present a new SIngle-scintillator Neutron and Gamma Ray spectrometer (SINGR) instrument for use with both passive and active measurement techniques. Here we discuss the application of SINGR for planetary exploration missions, however, hydrology, nuclear non-proliferation, and resource prospecting are all potential areas where the instrument could be applied. SINGR uses an elpasolite scintillato
Authors
Lena E. Heffern, Craig J. Hardgrove, Ann Parsons, E. B. Johnson, R. Starr, G. Stoddard, R. E. Blakeley, T. Prettyman, Travis S. J. Gabriel, H. Barnaby, J. Christian, M.A. Unzueta, C. Tate, A. Martin, J. Moersch

Past, present, and future of Mars Polar Science: Outcomes and outlook from the 7th International Conference on Mars Polar Science and Exploration

Mars Polar Science is a subfield of Mars science that encompasses all studies of the cryosphere of Mars and its interaction with the Martian environment. Every 4 yr, the community of scientists dedicated to this subfield meets to discuss new findings and debate open issues in the International Conference on Mars Polar Science and Exploration (ICMPSE). This paper summarizes the proceedings of the s
Authors
Patricio Becerra, Isaac B. Smith, Shannon M Hibbard, Chimira Andres, Jonathan Bapst, Ali Bramson, Peter Buhler, Andrea Coronato, Serina Diniega, Jeremy Emmett, Anna Grau Galofre, Clemence Herny, Melinda Kahre, J. Paul Knightly, Stefano Nerozzi, Alyssa Pascuzzo, Ganna Portyankina, Jorge Rabassa, Leslie Tamppari, Timothy N. Titus, Jennifer L Whitten, Zuriñe Yoldi

Workshop on terrestrial analogs for planetary exploration

Terrestrial analogs are an important part of the robotic and human exploration of the solar system. One of the main recommendations from a community survey conducted in 2019 was to hold a workshop to increase communication and share resources among scientists, engineers, data managers, educators, and students who are involved, or hope to be involved, in terrestrial analog studies.
Authors
Lauren A. Edgar, Amber Gullikson, M. Elise Rumpf, James Skinner

A preliminary regional geomorphologic map in Utopia Planitia of the Tianwen-1 Zhurong Landing Region

A geomorphologic map is an important step to understanding the geologic context and history of a site; here, we present an initial geomorphologic map for an area spanning 22°–26°N, 108°–112°E in the Utopia Planitia (UP) region on Mars. This site is of special interest because it contains the May 2021 landing site of the Zhurong rover from Tianwen-1. Utopia Planitia exhibits many lobate features th
Authors
Mackenzie M Mills, Alfred S. McEwen, Chris Okubo

Advancing cave detection using terrain analysis and thermal imagery

Since the initial experiments nearly 50 years ago, techniques for detecting caves using airborne and spacecraft acquired thermal imagery have improved markedly. These advances are largely due to a combination of higher instrument sensitivity, modern computing systems, and processor-intensive analytical techniques. Through applying these advancements, our goals were to: (1) Determine the efficacy o
Authors
J. Judson Wynne, Jeff Jenness, Derek Sonderegger, Timothy N. Titus, Murzy D. Jhabvala, Nathalie A. Cabrol

Evaluating stereo digital terrain model quality at Mars Rover Landing Sites with HRSC, CTX, and HiRISE Images

We have used high-resolution digital terrain models (DTMs) of two rover landing sites based on mosaicked images from the High-Resolution Imaging Science Experiment (HiRISE) camera as a reference to evaluate DTMs based on High-Resolution Stereo Camera (HRSC) and Context Camera (CTX) images. The Next-Generation Automatic Terrain Extraction (NGATE) matcher in the SOCET SET and GXP® commercial photogr
Authors
Randolph L. Kirk, David Mayer, Robin L. Fergason, Bonnie L. Redding, Donna M. Galuszka, Trent M. Hare, Klaus Gwinner

A geologic field guide to S P Mountain and its lava flow, San Francisco Volcanic Field, Arizona

IntroductionWe created this guide to introduce the user to the San Francisco Volcanic Field as a terrestrial analog site for planetary volcanic processes. For decades, the San Francisco Volcanic Field has been used to teach scientists to recognize the products of common types of volcanic eruptions and associated volcanic features. The volcanic processes and products observed in this volcanic field
Authors
Amber L. Gullikson, M. Elise Rumpf, Lauren A. Edgar, Laszlo P. Keszthelyi, James A. Skinner, Lisa Thompson