Publications
Filter Total Items: 910
Conceptual model for the removal of cold-trapped H2O ice on the Mars northern seasonal springtime polar cap
The transport of H2O ice along the retreating north polar seasonal CO2 ice cap has previously been modeled and observed. Spectral observations show that H2O ice forms on the interior of the seasonal cap, while thermal observations show these regions to be consistent with CO2 ice. Prior to the sublimation of the seasonal CO2, the observed H2O ice deposits are diminished—and because H2O ice sublimat
Authors
Timothy N. Titus, Kaj E. Williams, Glen E. Cushing
Planetary science decadal survey planetary mission concept study report: Ceres: Exploration of Ceres’ habitability
Dwarf planet Ceres is a compelling target as an evolved ocean world with, at least, regional brine reservoirs and potentially ongoing geological activity. As the most water-rich body in the inner solar system (in relative abundance), it is a representative of the population of planetesimals that brought volatiles and organics to the inner solar system. Situated in the Main Belt of asteroids, Ceres
Authors
J. C. Castillo-Rogez, John Brody, Michael T. Bland, Debra Buczkowski, Robert Grimm, A. Hendrix, Kelly Miller, Thomas Prettyman, Lynnae Quick, Carol Raymond, Jennifer Scully, Michael M. Sori, Yasuhito Sekine, David Williams, Michael Zolensky
Geomorphological evidence for a dry dust avalanche origin of slope streaks on Mars
Mars has several different types of slope feature that resemble aqueous flows. However, the current cold, dry conditions are inimical to liquid water, resulting in uncertainty about its role in modern surface processes. Dark slope streaks were among the first distinctive young slope features to be identified on Mars and the first with activity seen in orbital images. They form markings on steep sl
Authors
Colin M. Dundas
A newly emerging thermal area in Yellowstone
Yellowstone is a large restless caldera that contains many dynamic thermal areas that are the surface expression of the deeper magmatic system. In 2018, using a Landsat 8 nighttime thermal infrared image, we discovered the emergence of a new thermal area located near Tern Lake on the northeast margin of the Sour Creek dome. A high-spatial-resolution airborne visible image from August 2017 revealed
Authors
R. Greg Vaughan, Jefferson Hungerford, Bill Keller
The Moon as a climate-quality radiometric calibration reference
On-orbit calibration requirements for a space-based climate observing system include long-term sensor response stability and reliable inter-calibration of multiple sensors, both contemporaneous and in succession. The difficulties with achieving these for reflected solar wavelength instruments are well known. The Moon can be considered a diffuse reflector of sunlight, and its exceptional photometri
Authors
Thomas C. Stone, Hugh H. Kieffer, Constantine Lukashin, Kevin Turpie
Sparse subsurface radar reflectors in Hellas Planitia, Mars
Geomorphological features potentially related to subsurface ice, such as scalloped depressions, expanded craters, pedestal craters, and banded terrain, are present in and around Hellas Planitia, Mars. We present a radar survey of the region using the Shallow Radar (SHARAD) instrument on board the Mars Reconnaissance Orbiter (MRO) to identify candidate subsurface reflectors that may be due to the p
Authors
Claire W Cook, Ali M Bramson, Shane Byrne, John W Holt, Michael S Christoffersen, Donna Viola, Colin M. Dundas, Timothy A Goudge
The Mars Global Digital Dune Database (MGD3): Composition and stability
We present an expansion to the Mars Global Digital Dune Database (MGD3) describing 1) bulk dune field composition determined by fitting a mineral spectral library to Thermal Emission Spectra (TES) data, and 2) a morphologic stability index that measures the degree of non-aeolian modification that has eroded and stabilized each dune field. This paper describes results for these two components, prov
Authors
Lori K. Fenton, Amber Gullikson, Rosalyn Hayward, Heather Charles, Timothy N. Titus
Disk-integrated thermal properties of Ceres measured at the millimeter wavelengths
We observed Ceres at three epochs in 2015 November and 2017 September and October with Atacama Large Millimeter/submillimeter Array (ALMA) 12 m array and in 2017 October with the ALMA Compact Array (ACA), all at ~265 GHz continuum (wavelengths of ~1.1 mm) to map the temperatures of Ceres over a full rotation at each epoch. We also used 2017 October ACA observations to search for HCN. The disk-aver
Authors
Jian-Yang Li, Arielle Moullet, Timothy N. Titus, Henry H. Hsieh, Mark V. Sykes
A lacustrine paleoenvironment recorded at Vera Rubin ridge, Gale crater: Overview of the sedimentology and stratigraphy observed by the Mars Science Laboratory Curiosity rover
For ~500 Martian solar days (sols), the Mars Science Laboratory team explored Vera Rubin ridge (VRR), a topographic feature on the northwest slope of Aeolis Mons. Here we review the sedimentary facies and stratigraphy observed during sols 1,800–2,300, covering more than 100 m of stratigraphic thickness. Curiosity's traverse includes two transects across the ridge, which enables investigation of la
Authors
Lauren A. Edgar, Christopher M. Fedo, Sanjeev Gupta, Steve G. Banham, Abigail A. Fraeman, John P. Grotzinger, Kathryn M. Stack, Nathan T. Stein, Kristen A. Bennett, Frances Rivera-Hernandez, Vivian Z. Sun, Kenneth S. Edgett, David M. Rubin, Christopher H House, Jason K. Van Beek
Planetary sensor models interoperability using the community sensor model specification
This paper presents the photogrammetric foundations upon which the Community Sensor Model specification depends, describes common coordinate system and reference frame transformations that support conversion between image sensor (charge‐coupled device) coordinates to some arbitrary body coordinate, and describes the U.S. Geological Survey Astrogeology Community Sensor Model implementation (https:/
Authors
Jason Laura, Jesse Mapel, Trent M. Hare
Preparing for geophysical science on the surface of the moon enabled by Artemis
Geophysical methods have been extremely successful in identifying resources on Earth as they provide a means of characterizing and mapping the sub-surface using data gathered on and above the target structures. Geophysics on the Moon will be an important tool for identifying key targets for geological prospecting, scientific sampling, assessing hazards and risks to crew and infrastructure, and det
Authors
Nicholas Schmerr, Jacob A. Richardson, R. Ghent, Matt Seigler, Molly Wasser, Patrick Wheeley, D. Buczkowski, Lynne Carter, Chuck Connor, Laura Connor, Jacob E. Bleacher, M. Fouch, D. Baker, T. Hurford, L. Jozwiak, Sarah Kruse, V. Lekic, A. Naids, Ryan Porter, L. Montesi, Derek Richardson, M. Elise Rumpf, J. Sunshine, Norbert Schorghofer, S. Goossens, Nicole Whelley, D. Wyrick, W. Zhu, Ernie Bell, J. DeMartini, D. Coan, D. Akin, Barbara Cohen, E. Mazarico, Clive Neal, M. Panning, Noah Petro, B. Strauss, Renee Weber, T. Glotch, A. Hendrix, A. Parker, Sarah Wright
An aeolian grainflow model for Martian Recurring Slope Lineae
Recurring Slope Lineae (RSL) on Mars have been enigmatic since their discovery; their behavior resembles a seeping liquid but sources of water remain puzzling. This work demonstrates that the properties of RSL are consistent with observed behaviors of Martian and terrestrial aeolian processes. Specifically, RSL are well-explained as flows of sand that remove a thin coating of dust. Observed RSL pr
Authors
Colin M. Dundas