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Publications

Filter Total Items: 915

Mars Reconnaissance Orbiter and Opportunity observations of the Burns formation: crater hopping at Meridiani Planum

Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral (1.0–2.65 µm) along-track oversampled observations covering Victoria, Santa Maria, Endeavour, and Ada craters were processed to 6 m/pixel and used in combination with Opportunity observations to detect and map hydrated Mg and Ca sulfate minerals in the Burns formation. The strongest spectral absorption features were found to be ass
Authors
R.E. Arvidson, J.F. Bell, J.G. Catalano, B. C. Clark, V.K. Fox, Ralf Gellert, J.P. Grotzinger, E.A. Guinness, Kenneth E. Herkenhoff, A.H. Knoll, M.G.A. Lapotre, S. M. McLennan, D. W. Ming, R.V. Morris, S.L. Murchie, K. E. Powell, M. D. Smith, S. W. Squyres, M.J. Wolff, J.J. Wray

Enumeration of Mars years and seasons since the beginning of telescopic exploration

A clarification for the enumeration of Mars Years prior to 1955 is presented, along with a table providing the Julian dates associated with Ls = 0° for Mars Years -183 (beginning of the telescopic study of Mars) to 100. A practical algorithm for computing Ls as a function of the Julian Date is provided. No new science results are presented
Authors
Sylvain Piqueux, Shane Byrne, Timothy N. Titus, Candice J. Hansen, Hugh H. Kieffer

Expanded secondary craters in the Arcadia Planitia region, Mars: evidence for tens of Myr-old shallow subsurface ice

A range of observations indicates widespread subsurface ice throughout the mid and high latitudes of Mars in the form of both pore-filling and excess ice. It is generally thought that this ice was recently emplaced and is not older than a hundred thousand to a few millions of years old based on ice stability and orbital-induced climate change. We analyze the distribution of subsurface ice in Arcad
Authors
Donna Viola, Alfred S. McEwen, Colin M. Dundas, Shane Byrne

Forming Ganymede’s grooves at smaller strain: Toward a self-consistent local and global strain history for Ganymede

The ubiquity of tectonic features formed in extension, and the apparent absence of ones formed in contraction, has led to the hypothesis that Ganymede has undergone global expansion in its past. Determining the magnitude of such expansion is challenging however, and extrapolation of locally or regionally inferred strains to global scales often results in strain estimates that exceed those based on
Authors
Michael T. Bland, W. B. McKinnon

Ceres: predictions for near-surface water ice stability and implications for plume generating processes

This paper will constrain the possible sources and processes for the formation of recently observed H2O vapor plumes above the surface of the dwarf planet Ceres. Two hypotheses have been proposed: (1) cryovolcanism where the water source is the mantle and the heating source is still unknown or (2) comet-like sublimation where near-surface water ice is vaporized by seasonally increasing solar insol
Authors
Timothy N. Titus

Context of ancient aqueous environments on Mars from in situ geologic mapping at Endeavour Crater

Using the Mars Exploration Rover Opportunity, we have compiled one of the first field geologic maps on Mars while traversing the Noachian terrain along the rim of the 22 km diameter Endeavour Crater (Latitude −2°16′33″, Longitude −5°10′51″). In situ mapping of the petrographic, elemental, structural, and stratigraphic characteristics of outcrops and rocks distinguishes four mappable bedrock lithol
Authors
L.S. Crumpler, R. E. Arvidson, J. Bell, B. C. Clark, B. A. Cohen, W. H. Farrand, Ralf Gellert, M. Golombek, J. A. Grant, E. Guinness, Kenneth E. Herkenhoff, J. R. Johnson, B. Jolliff, D. W. Ming, D. W. Mittlefehldt, T. Parker, J. W. Rice, S. W. Squyres, R. Sullivan, A. S. Yen

Micrometer-scale U–Pb age domains in eucrite zircons, impact re-setting, and the thermal history of the HED parent body

Meteoritic zircons are rare, but some are documented to occur in asteroidal meteorites, including those of the howardite–eucrite–diogenite (HED) achondrite clan (Rubin, A. [1997]. Meteorit. Planet. Sci. 32, 231–247). The HEDs are widely considered to originate from the Asteroid 4 Vesta. Vesta and the other large main belt asteroids record an early bombardment history. To explore this record, we de
Authors
M.D. Hopkins, S.J. Mojzsis, W.F. Bottke, Oleg Abramov

Astronomical observations of volatiles on asteroids

We have long known that water and hydroxyl are important components in meteorites and asteroids. However, in the time since the publication of Asteroids III, evolution of astronomical instrumentation, laboratory capabilities, and theoretical models have led to great advances in our understanding of H2O/OH on small bodies, and spacecraft observations of the Moon and Vesta have important implication
Authors
Andrew S. Rivkin, Humberto Campins, Joshua P. Emery, Ellen S. Howell, Javier Licandro, Driss Takir, Faith Vilas

Understanding the signature of rock coatings in laser-induced breakdown spectroscopy data

Surface compositional features on rocks such as coatings and weathering rinds provide important information about past aqueous environments and water–rock interactions. The search for these features represents an important aspect of the Curiosity rover mission. With its unique ability to do fine-scale chemical depth profiling, the ChemCam laser-induced breakdown spectroscopy instrument (LIBS) onbo
Authors
Nina L. Lanza, Ann M. Ollila, Agnès Cousin, Roger C. Wiens, Samuel M. Clegg, Nicolas Mangold, Nathan Bridges, Daniel Cooper, Mariek E. Schmidt, Jeffrey Berger, Raymond E. Arvidson, Noureddine Melikechi, Horton E. Newsom, Robert Tokar, Craig Hardgrove, Alissa Mezzacappa, Ryan S. Jackson, Benton C. Clark, Olivier Forni, Sylvestre Maurice, Marion Nachon, Ryan B. Anderson, Jennifer Blank, Matthew Deans, Dorothea Delapp, Richard Léveillé, Rhonda McInroy, Ronald Martinez, Pierre-Yves Meslin, Patrick Pinet

Asteroid photometry

Asteroid photometry has three major applications: providing clues about asteroid surface physical properties and compositions, facilitating photometric corrections, and helping design and plan ground-based and spacecraft observations. The most significant advances in asteroid photometry in the past decade were driven by spacecraft observations that collected spatially resolved imaging and spectro
Authors
Jian-Yang Li, Paul Helfenstein, Bonnie J. Buratti, Driss Takir, Beth Ellen Clark

Small crater modification on Meridiani Planum and implications for erosion rates and climate change on Mars

A morphometric and morphologic catalog of ~100 small craters imaged by the Opportunity rover over the 33.5 km traverse between Eagle and Endeavour craters on Meridiani Planum shows craters in six stages of degradation that range from fresh and blocky to eroded and shallow depressions ringed by planed off rim blocks. The age of each morphologic class from <50–200 ka to ~20 Ma has been determined fr
Authors
M.P. Golombek, N.H. Warner, V. Ganti, M.P. Lamb, T. J. Parker, Robin L. Fergason, R. Sullivan

A new analysis of Mars "Special Regions": findings of the Second MEPAG Special Regions Science Analysis Group (SR-SAG2)

A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understan
Authors
John D. Rummel, David W. Beaty, Melissa A. Jones, Corien Bakermans, Nadine G. Barlow, Penelope J. Boston, Vincent F. Chevrier, Benton C. Clark, Jean-Pierre P. de Vera, Raina V. Gough, John E. Hallsworth, James W. Head, Victoria J. Hipkin, Thomas L. Kieft, Alfred S. McEwen, Michael T. Mellon, Jill A. Mikucki, Wayne L. Nicholson, Christopher R. Omelon, Ronald Peterson, Eric E. Roden, Barbara Sherwood Lollar, Kenneth L. Tanaka, Donna Viola, James J. Wray