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Publications

Filter Total Items: 915

Morphological indicators of a mascon beneath Ceres' largest crater, Kerwan

Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long‐term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from
Authors
Michael T. Bland, Anton Ermakov, Carol A. Raymond, David A. Williams, Tim J. Bowling, F. Preusker, Ryan S. Park, Simone Marchi, Julie C. Castillo-Rogez, R.R. Fu, Christopher T. Russell

Image simulation and assessment of the colour and spatial capabilities of the Colour and Stereo Surface Imaging System (CaSSIS) on the ExoMars Trace Gas Orbiter

This study aims to assess the spatial and visible/near-infrared (VNIR) colour/spectral capabilities of the 4-band Colour and Stereo Surface Imaging System (CaSSIS) aboard the ExoMars 2016 Trace Grace Orbiter (TGO). The instrument response functions for the CaSSIS imager was used to resample spectral libraries, modelled spectra and to construct spectrally (i.e., in I/F space) and spatially consiste
Authors
Livio L. Tornabene, Frank P. Seelos, Antoine Pommerol, Nicolas Thomas, Christy M. Caudill, Patricio Becerra, John C. Bridges, Shane Byrne, Marco Cardinale, Matthew Chojnacki, Susan J. Conway, Gabriele Cremonese, Colin M. Dundas, M. R. El-Maarry, Jennifer Fernando, Candice J. Hansen, Kayle Hansen, Tanya N. Harrison, Rachel Henson, Lucia Marinangeli, Alfred S. McEwen, Maurizio Pajola, Sarah S. Sutton, James J. Wray

Planetary dune workshop expands to include subaqueous processes

Dune-like structures appear in the depths of Earth’s oceans, across its landscapes, and in the extremities of the solar system beyond. Dunes rise up under the thick dense atmosphere of Venus, and they have been found under the almost unimaginably ephemeral atmosphere of a comet.
Authors
Timothy N. Titus, Gerald Bryant, David M. Rubin

Revised recommended methods for analyzing crater size-frequency distributions

Impact crater populations crucially help us to understand solar system dynamics, planetary surface histories, and surface modification processes. A single previous effort to standardize how crater data are displayed in graphs, tables, and archives, was in a 1978 NASA report by the Crater Analysis Techniques Working Group, published in 1979 in Icarus. The report had a significant lasting effect, bu
Authors
Stuart J. Robbins, Jamie D. Riggs, Brian P. Weaver, Edward B. Bierhaus, Clark R. Chapman, Michelle R. Kirchoff, Kelsi N. Singer, Lisa Gaddis

Detecting geothermal anomalies and evaluating LST geothermal component by combining thermal remote sensing time series and land surface model data

This paper explores for the first time the possibilities to use two land surface temperature (LST) time series of different origins (geostationary Meteosat Second Generation satellite data and Noah land surface modelling, LSM), to detect geothermal anomalies and extract the geothermal component of LST, the LSTgt. We hypothesize that in geothermal areas the LSM time series will underestimate the LS
Authors
Mireia Romaguera, R. Greg Vaughan, J. Ettema, E. Izquierdo-Verdiguier, C. A. Hecker, F.D. van der Meer

Evidence for the interior evolution of Ceres from geologic analysis of fractures

Ceres is the largest asteroid belt object, and the Dawn spacecraft observed Ceres since 2015. Dawn observed two morphologically distinct linear features on Ceres's surface: secondary crater chains and pit chains. Pit chains provide unique insights into Ceres's interior evolution. We interpret pit chains called the Samhain Catenae as the surface expression of subsurface fractures. Using the pit cha
Authors
Jennifer E. C. Scully, Debra Buczkowski, Nico Schmedemann, Carol A. Raymond, Julie C. Castillo-Rogez, Scott King, Michael T. Bland, Anton Ermakov, D.P. O'Brien, S. Marchi, A. Longobardo, C.T. Russell, R.R. Fu, M. Neveu

Basalt–trachybasalt samples in Gale Crater, Mars

The ChemCam instrument on the Mars Science Laboratory (MSL) rover, Curiosity, observed numerous igneous float rocks and conglomerate clasts, reported previously. A new statistical analysis of single‐laser‐shot spectra of igneous targets observed by ChemCam shows a strong peak at ~55 wt% SiO2 and 6 wt% total alkalis, with a minor secondary maximum at 47–51 wt% SiO2 and lower alkali content. The cen
Authors
Peter H. Edwards, John C. Bridges, Roger C. Wiens, Ryan B. Anderson, M. Darby Dyar, Martin Fisk, Lucy Thompson, Patrick J. Gasda, Justin Filiberto, Susanne P. Schwenzer, Diana L. Blaney, Ian Hutchinson

Preface: The lunar reconnaissance orbiter

When the call for papers for a special issue of Icarus devoted to analysis of data from the Lunar Reconnaissance Orbiter mission was announced in March 2015 we envisioned a single issue with only a possibility of a second. We certainly were gratified by the response from within and outside the LRO instrument teams such that we were compelled to publish this the third and final volume. It is a test
Authors
John W Keller, Lisa R. Gaddis, Noah E. Petro, Oded Aharonson

Correcting spacecraft jitter in HiRISE images

Mechanical oscillations or vibrations on spacecraft, also called pointing jitter, cause geometric distortions and/or smear in high resolution digital images acquired from orbit. Geometric distortion is especially a problem with pushbroom type sensors, such as the High Resolution Imaging Science Experiment (HiRISE) instrument on board the Mars Reconnaissance Orbiter (MRO). Geometric distortions occ
Authors
S. S. Sutton, A.K. Boyd, Randolph L. Kirk, Debbie Cook, Jean Backer, A. Fennema, R. Heyd, A.S. McEwen, S.D. Mirchandani

Community tools for cartographic and photogrammetric processing of Mars Express HRSC images

The High Resolution Stereo Camera (HRSC) on the Mars Express orbiter (Neukum et al. 2004) is a multi-line pushbroom scanner that can obtain stereo and color coverage of targets in a single overpass, with pixel scales as small as 10 m at periapsis. Since commencing operations in 2004 it has imaged ~ 77 % of Mars at 20 m/pixel or better. The instrument team uses the Video Image Communication And Ret
Authors
Randolph L. Kirk, Elpitha Howington-Kraus, Kenneth L. Edmundson, Bonnie L. Redding, Donna M. Galuszka, Trent M. Hare, K. Gwinner

Spatial data analytics on heterogeneous multi- and many-core parallel architectures using python

Parallel vector spatial analysis concerns the application of parallel computational methods to facilitate vector-based spatial analysis. The history of parallel computation in spatial analysis is reviewed, and this work is placed into the broader context of high-performance computing (HPC) and parallelization research. The rise of cyber infrastructure and its manifestation in spatial analysis as C
Authors
Jason R. Laura, Sergio J. Rey

CO2 cycle

This chapter discusses the use of models, observations, and laboratory experiments to understand the cycling of CO2 between the atmosphere and seasonal Martian polar caps. This cycle is primarily controlled by the polar heat budget, and thus the emphasis here is on its components, including solar and infrared radiation, the effect of clouds (water- and CO2-ice), atmospheric transport, and subsurfa
Authors
Timothy N. Titus, Shane Byrne, Anthony Colaprete, Francois Forget, Timothy I. Michaels, Thomas H. Prettyman