Publications
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CO2 jets formed by sublimation beneath translucent slab ice in Mars' seasonal south polar ice cap CO2 jets formed by sublimation beneath translucent slab ice in Mars' seasonal south polar ice cap
The martian polar caps are among the most dynamic regions on Mars, growing substantially in winter as a significant fraction of the atmosphere freezes out in the form of CO2 ice. Unusual dark spots, fans and blotches form as the south-polar seasonal CO2 ice cap retreats during spring and summer. Small radial channel networks are often associated with the location of spots once the ice...
Authors
Hugh H. Kieffer, Phillip R. Christensen, Timothy N. Titus
Titan Radar Mapper observations from Cassini's T3 fly-by Titan Radar Mapper observations from Cassini's T3 fly-by
Cassini's Titan Radar Mapper imaged the surface of Saturn's moon Titan on its February 2005 fly-by (denoted T3), collecting high-resolution synthetic-aperture radar and larger-scale radiometry and scatterometry data. These data provide the first definitive identification of impact craters on the surface of Titan, networks of fluvial channels and surficial dark streaks that may be...
Authors
C. Elachi, S. Wall, M. Janssen, E. Stofan, R. Lopes, Randolph L. Kirk, R. Lorenz, J. Lunine, F. Paganelli, Laurence A. Soderblom, C. Wood, L. Wye, H. Zebker, Y. Anderson, S. Ostro, M. Allison, R. Boehmer, P. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, W. Johnson, K. Kelleher, D. Muhleman, G. Picardi, F. Posa, L. Roth, R. Seu, S. Shaffer, B. Stiles, S. Vetrella, R. West
Two years at Meridiani Planum: Results from the Opportunity Rover Two years at Meridiani Planum: Results from the Opportunity Rover
The Mars Exploration Rover Opportunity has spent more than 2 years exploring Meridiani Planum, traveling ∼8 kilometers and detecting features that reveal ancient environmental conditions. These include well-developed festoon (trough) cross-lamination formed in flowing liquid water, strata with smaller and more abundant hematite-rich concretions than those seen previously, possible relict...
Authors
S. W. Squyres, A.H. Knoll, R. E. Arvidson, B. C. Clark, J.P. Grotzinger, B.L. Jolliff, S. M. McLennan, N. Tosca, J.F. Bell, W. M. Calvin, W. H. Farrand, T.D. Glotch, M.P. Golombek, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, H.Y. McSween, A. S. Yen
The heartbeat of the volcano: The discovery of episodic activity at Prometheus on Io The heartbeat of the volcano: The discovery of episodic activity at Prometheus on Io
The temporal signature of thermal emission from a volcano is a valuable clue to the processes taking place both at and beneath the surface. The Galileo Near Infrared Mapping Spectrometer (NIMS) observed the volcano Prometheus, on the jovian moon Io, on multiple occasions between 1996 and 2002. The 5 micron (μm) brightness of this volcano shows considerable variation from orbit to orbit...
Authors
Ashley G. Davies, Lionel Wilson, Dennis Matson, Giovanni Leone, Laszlo P. Keszthelyi, Windy L. Jaeger
Sedimentary textures formed by aqueous processes, Erebus crater Meridiani Planum, Mars Sedimentary textures formed by aqueous processes, Erebus crater Meridiani Planum, Mars
New observations at Erebus crater (Olympia outcrop) by the Mars Exploration Rover Opportunity between sols 671 and 735 (a sol is a martian day) indicate that a diverse suite of primary and penecontemporaneous sedimentary structures is preserved in sulfate-rich bedrock. Centimeter-scale trough (festoon) cross-lamination is abundant, and is better expressed and thicker than previously...
Authors
J. Grotzinger, J. Bell, Kenneth E. Herkenhoff, J. Johnson, A. Knoll, E. McCartney, S. McLennan, J. Metz, Jeff Moore, S. Squyres, R. Sullivan, O. Ahronson, R. Arvidson, B. Joliff, M. Golombek, K. Lewis, T. Parker, J. Soderblom
Cartography for lunar exploration: 2006 status and planned missions Cartography for lunar exploration: 2006 status and planned missions
The initial spacecraft exploration of the Moon in the 1960s–70s yielded extensive data, primarily in the form of film and television images, that were used to produce a large number of hardcopy maps by conventional techniques. A second era of exploration, beginning in the early 1990s, has produced digital data including global multispectral imagery and altimetry, from which a new...
Authors
Randolph L. Kirk, Brent A. Archinal, Lisa R. Gaddis, Mark R. Rosiek
Flood lavas on Earth, Io and Mars Flood lavas on Earth, Io and Mars
Flood lavas are major geological features on all the major rocky planetary bodies. They provide important insight into the dynamics and chemistry of the interior of these bodies. On the Earth, they appear to be associated with major and mass extinction events. It is therefore not surprising that there has been significant research on flood lavas in recent years. Initial models suggested...
Authors
Laszlo P. Keszthelyi, Stephen Self, Thorvaldur Thordarson
Sulfate deposition in subsurface regolith in Gusev crater, Mars Sulfate deposition in subsurface regolith in Gusev crater, Mars
Excavating into the shallow Martian subsurface has the potential to expose stratigraphic layers and mature regolith, which may hold a record of more ancient aqueous interactions than those expected under current Martian surface conditions. During the Spirit rover's exploration of Gusev crater, rover wheels were used to dig three trenches into the subsurface regolith down to 6-11 cm depth...
Authors
A. Wang, L.A. Haskin, S. W. Squyres, B.L. Jolliff, L. Crumpler, Ralf Gellert, C. Schroder, Kenneth E. Herkenhoff, J. Hurowitz, N.J. Tosca, W. H. Farrand, R. Anderson, A.T. Knudson
Soil grain analyses at Meridiani Planum, Mars Soil grain analyses at Meridiani Planum, Mars
Grain‐size analyses of the soils at Meridiani Planum have been used to identify rock sources for the grains and provide information about depositional processes under past and current conditions. Basaltic sand, dust, millimeter‐size hematite‐rich spherules interpreted as concretions, spherule fragments, coated partially buried spherules, basalt fragments, sedimentary outcrop fragments...
Authors
C.M. Weitz, R. C. Anderson, J.F. Bell, W. H. Farrand, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, R.V. Morris, S. W. Squyres, R.J. Sullivan
The HRSC DTM test The HRSC DTM test
The High Resolution Stereo Camera (HRSC) has been orbiting the planet Mars since January 2004 onboard the ESA Mars Express mission and delivers imagery which is being used for topographic mapping of the planet. The HRSC team is currently conducting a systematic inter-comparison of different alternatives for the production of high resolution Digital Terrain Models (DTMs) from the...
Authors
Christian Heipke, Jurgen Oberst, Jeorg Albertz, Maria Attwenger, Peter Dorninger, Egon Dorrer, M. Ewe, Stephan Gehrke, Klaus Gwinner, H. Hirschmuller, J.R. Kim, Randolph L. Kirk, H. Mayer, Jan-Peter Muller, Rajagopalan Rengarajan, M. Rentsch, R. Schmidt, Frank Scholten, J. Shan, Michael Spiegel, M. Wahlisch, Gerhard Neukum
Rocks of the Columbia Hills Rocks of the Columbia Hills
The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a...
Authors
S. W. Squyres, R. E. Arvidson, D.L. Blaney, B. C. Clark, L. Crumpler, W. H. Farrand, S. Gorevan, Kenneth E. Herkenhoff, J. Hurowitz, A. Kusack, H.Y. McSween, D. W. Ming, R.V. Morris, S. W. Ruff, A. Wang, A. Yen
Physical properties of the Mars Exploration Rover landing sites as inferred from Mini-TES-derived thermal inertia Physical properties of the Mars Exploration Rover landing sites as inferred from Mini-TES-derived thermal inertia
The Miniature Thermal Emission Spectrometer (Mini‐TES) on board the two Mars Exploration Rovers provides the first opportunity to observe thermal properties from the Martian surface, relate these properties to orbital data, and perform soil conductivity experiments under Martian conditions. The thermal inertias of soils, bedforms, and rock at each landing site were derived to quantify...
Authors
R.L. Fergason, P. R. Christensen, J.F. Bell, M.P. Golombek, Kenneth E. Herkenhoff, H. H. Kieffer