Publications
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In situ detection of boron by ChemCam on Mars
We report the first in situ detection of boron on Mars. Boron has been detected in Gale crater at levels <0.05 wt % B by the NASA Curiosity rover ChemCam instrument in calcium‐sulfate‐filled fractures, which formed in a late‐stage groundwater circulating mainly in phyllosilicate‐rich bedrock interpreted as lacustrine in origin. We consider two main groundwater‐driven hypotheses to explain the pres
Authors
Patrick J. Gasda, Ethan B. Haldeman, Roger C. Wiens, William Rapin, Thomas F. Bristow, John C. Bridges, Susanne P. Schwenzer, Benton C. Clark, Kenneth E. Herkenhoff, Jens Frydenvang, Nina L. Lanza, Sylvestre Maurice, Samuel M. Clegg, Dorothea M. Delapp, Veronica L. Sanford, Madeleine R. Bodine, Rhonda McInroy
The planetary data system
In the early 1980s, the Space Science Board (SSB) of the National Research Council was concerned about the poor and inconsistent treatment of scientific information returned from NASA’s space science missions. The SSB formed a panel [The Committee on Data Management and Computation (CODMAC)] to assess the situation and make recommendations to NASA for improvements. The CODMAC panel issued a report
Authors
Charles Acton, Susan Slavney, Raymond E. Arvidson, Lisa R. Gaddis, Mitchell Gordon, Susan Lavoie
An evaluation of sampling and full enumeration strategies for Fisher Jenks classification in big data settings
Large data contexts present a number of challenges to optimal choropleth map classifiers. Application of optimal classifiers to a sample of the attribute space is one proposed solution. The properties of alternative sampling-based classification methods are examined through a series of Monte Carlo simulations. The impacts of spatial autocorrelation, number of desired classes, and form of sampling
Authors
Sergio J. Rey, Philip A. Stephens, Jason R. Laura
The U.S. Geological Survey Astrogeology Science Center
In 1960, Eugene Shoemaker and a small team of other scientists founded the field of astrogeology to develop tools and methods for astronauts studying the geology of the Moon and other planetary bodies. Subsequently, in 1962, the U.S. Geological Survey Branch of Astrogeology was established in Menlo Park, California. In 1963, the Branch moved to Flagstaff, Arizona, to be closer to the young lava fl
Authors
Laszlo P. Kestay, R. Greg Vaughan, Lisa R. Gaddis, Kenneth E. Herkenhoff, Justin Hagerty
Geomorphology of comet 67P/Churyumov–Gerasimenko
We present a global geomorphological map of comet 67P/Churyumov–Gerasimenko (67P/C-G) using data acquired by the Rosetta Orbiter’s OSIRIS Narrow Angle Camera. The images used in our study were acquired between 2014 August and 2015 May, before 67P/C-G passed through perihelion. Imagery of the Southern hemisphere was included in our study, allowing us to compare the contrasting hemispheres of 67P/C-
Authors
Samuel P. D. Birch, Y. Tang, A. G. Hayes, Randolph L. Kirk, D. Bodewitz, H. Campins, Y. Fernandez, R. de Freitas Bart, N. W. Kutsop, H. Sierks, J. M. Soderblom, S. W. Squyres, J.-B. Vincent
Towards a planetary spatial data infrastructure
Planetary science is the study of planets, moons, irregular bodies such as asteroids and the processes that create and modify them. Like terrestrial sciences, planetary science research is heavily dependent on collecting, processing and archiving large quantities of spatial data to support a range of activities. To address the complexity of storing, discovering, accessing, and utilizing spatial da
Authors
Jason Laura, Trent M. Hare, Lisa R. Gaddis, Robin L. Fergason, James Skinner, Justin Hagerty, Brent Archinal
Shaler: in situ analysis of a fluvial sedimentary deposit on Mars
This paper characterizes the detailed sedimentology of a fluvial sandbody on Mars for the first time and interprets its depositional processes and palaeoenvironmental setting. Despite numerous orbital observations of fluvial landforms on the surface of Mars, ground-based characterization of the sedimentology of such fluvial deposits has not previously been possible. Results from the NASA Mars Scie
Authors
Lauren A. Edgar, Sanjeev Gupta, David M. Rubin, Kevin W. Lewis, Gary A. Kocurek, Ryan Anderson, James F. Bell, Gilles Dromart, Kenneth S. Edgett, John P. Grotzinger, Craig Hardgrove, Linda C. Kah, Richard A. LeVeille, Michael C. Malin, Nicholas Mangold, Ralph E. Milliken, Michelle Minitti, Marisa C. Palucis, Melissa Rice, Scott K. Rowland, Juergen Schieber, Kathryn M. Stack, Dawn Y. Sumner, Roger C. Wiens, Rebecca M.E. Williams, Amy J. Williams
The morphology of transverse aeolian ridges on Mars
A preliminary survey of publicly released high resolution digital terrain models (DTMs) produced by the High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter identified transverse aeolian ridges (TARs) in 154 DTMs in latitudes from 50°S to 40°N. Consistent with previous surveys, the TARs identified in HiRISE DTMs are found at all elevations, irrespective of the
Authors
Paul Geissler, Justin T. Wilgus
Geomorphological evidence for ground ice on dwarf planet Ceres
Five decades of observations of Ceres suggest that the dwarf planet has a composition similar to carbonaceous meteorites and may have an ice-rich outer shell protected by a silicate layer. NASA’s Dawn spacecraft has detected ubiquitous clays, carbonates and other products of aqueous alteration across the surface of Ceres, but surprisingly it has directly observed water ice in only a few areas. Her
Authors
Britney E. Schmidt, Kynan H.G. Hughson, Heather T. Chilton, Jennifer E. C. Scully, Thomas Platz, Andreas Nathues, Hanna Sizemore, Michael T. Bland, Shane Byrne, Simone Marchi, David O'Brien, Norbert Schorghofer, Harald Hiesinger, Ralf Jaumann, Jan Hendrick Pasckert, Justin D. Lawrence, Debra Buzckowski, Julie C. Castillo-Rogez, Mark V. Sykes, Paul M. Schenk, Maria-Cristina DeSanctis, Giuseppe Mitri, Michelangelo Formisano, Jian-Yang Li, Vishnu Reddy, Lucille Le Corre, Christopher T. Russell, Carol A. Raymond
Crater density differences: Exploring regional resurfacing, secondary crater populations, and crater saturation equilibrium on the moon
The global population of lunar craters >20 km in diameter was analyzed by Head et al., (2010) to correlate crater distribution with resurfacing events and multiple impactor populations. The work presented here extends the global crater distribution analysis to smaller craters (5–20 km diameters, n = 22,746). Smaller craters form at a higher rate than larger craters and thus add granularity to age
Authors
R. Z. Povilaitis, M. S. Robinson, C. H. van der Bogert, Harald Hiesinger, H. M. Meyer, Lillian R. Ostrach
Large crater clustering tool
In this paper we present the Large Crater Clustering (LCC) tool set, an ArcGIS plugin that supports the quantitative approximation of a primary impact location from user-identified locations of possible secondary impact craters or the long-axes of clustered secondary craters. The identification of primary impact craters directly supports planetary geologic mapping and topical science studies where
Authors
Jason Laura, James A. Skinner, Marc A. Hunter
Diagenetic silica enrichment and late-stage groundwater activity in Gale crater, Mars
Diagenetic silica enrichment in fracture-associated halos that crosscut lacustrine and unconformably overlying aeolian sedimentary bedrock is observed on the lower north slope of Aeolis Mons in Gale crater, Mars. The diagenetic silica enrichment is colocated with detrital silica enrichment observed in the lacustrine bedrock yet extends into a considerably younger, unconformably draping aeolian san
Authors
Jens Frydenvang, Patrick J. Gasda, Joel A. Hurowitz, John P. Grotzinger, Roger C. Wiens, Horton E. Newsom, Ken S. Edgett, Jessica Watkins, John C. Bridges, Sylvestre Maurice, Martin R. Fisk, Jeffrey R. Johnson, William Rapin, Nathan Stein, Sam M. Clegg, S. P. Schwenzer, C. Bedford, P. Edwards, Nicolas Mangold, Agnès Cousin, Ryan Anderson, Valerie Payre, David Vaniman, David Blake, Nina L. Lanza, Sanjeev Gupta, Jason K. Van Beek, Violaine Sautter, Pierre-Yves Meslin, Melissa Rice, Ralf Milliken, Ralf Gellert, Lucy Thompson, Ben C. Clark, Dawn Y. Sumner, Abigail A. Fraeman, Kjartan M Kinch, Morten B. Madsen, Igor Mitofranov, Insoo Jun, Fred J. Calef, Ashwin R. Vasavada