Publications
Filter Total Items: 910
Preliminary geological assessment of the Northern edge of Ultimi Lobe, Mars South Polar layered deposits
We have examined the local base of the south polar layered deposits (SPLD) exposed in the bounding scarp near 72°–74°S, 215°–230°W where there is a clear unconformable contact with older units. Sections of layering up to a kilometer thick were examined along the bounding scarp, permitting an estimate of the thinnest individual layers yet reported in the SPLD. Rhythmic layering is also present loca
Authors
B. Murray, M. Koutnik, S. Byrne, Laurence A. Soderblom, Kenneth E. Herkenhoff, K. L. Tanaka
Lunar Transient Phenomena: What do the Clementine Images Reveal?
Lunar Transient Phenomena (LTP) have been reported for at least 450 years. The events range from bright flashes, to reddish or bluish glows, to obscurations. Gaseous spectra and photometric measurements of the events have been obtained. Several theories have been offered as explanations for LTP, including residual volcanic activity or outgassing, bombardment by energetic particles, and piezoelectr
Authors
Bonnie J. Buratti, Timothy H. McConnochie, Sascha B. Calkins, John K. Hillier, Kenneth E. Herkenhoff
Recent planetary topographic mapping at the USGS, Flagstaff: Moon, Mars, Venus, and beyond
We are currently using stereophotogrammetric techniques to compile digital topographic models of parts of the Moon, Mars, Venus, and the asteroid Eros in support of the NASA program of planetary exploration. This work requires the synergistic use of the USGS digital cartographic software system ISIS for data ingestion and calibration steps, along with the commercial software SOCET SET for “photogr
Authors
Randolph L. Kirk, Elpitha Howington-Kraus, Mark R. Rosiek
Digital elevation models derived from small format lunar images
No abstract available.
Authors
Mark R. Rosiek, Randolph L. Kirk, Elpitha Howington-Kraus
Results of the Galileo solid state imaging (SSI) experiment
We present a brief synopsis of the nature of SSI data that was taken during the nominal Galileo mission. Significant results are briefly described. These include evidence for geologic activity on Europa that supports the hypothesis of liquid water under a thin ice shell; a demonstration of the ubiquitous presence of a thick crust and high temperature silicate volcanism on Io; a demonstration that,
Authors
Michael J.S. Belton, C.D. Anger, M. H. Carr, C. R. Chapman, M. E. Davies, R. Greeley, R.J. Greenberg, J.W. Head, K.P. Klaasen, G. Neukum, C.B. Pilcher, P. C. Thomas, J. Veverka, P.J. Gierasch, A.P. Ingersoll, F. P. Fanale, Alfred S. McEwen, D. Morrison, G. Schubert, R.F. Beebe, J.A. Burns, T. V. Johnson, R.A. West, W. Ip, Michael McElroy, G.S. Orton
Compositional analyses of small lunar pyroclastic deposits using Clementine multispectral data
Clementine ultraviolet-visible (UVVIS) data are used to examine the compositions of 18 pyroclastic deposits (15 small, three large) at 13 sites on the Moon. Compositional variations among pyroclastic deposits largely result from differing amounts of new basaltic (or juvenile) material and reworked local material entrained in their ejecta upon eruption. Characterization of pyroclastic deposit compo
Authors
Lisa R. Gaddis, Bernard Ray Hawke, Mark S. Robinson, Cassandra Coombs
Volcanism and ice interactions on Earth and Mars
Volcano/ice interactions produce meltwater. Meltwater can enter the groundwater cycle and under the influence of hydrothermal systems, it can be later discharged to form channels and valleys or cycled upward to melt permafrost. Water or ice-saturated ground can erupt into phreatic craters when covered by lava. Violent mixing of meltwater and volcanic material and rapid release can generate lahars
Authors
Mary G. Chapman, Carlton C. Allen, Magnus T. Gudmundsson, Virginia C. Gulick, Sveinn P. Jakobsson, Baerbel K. Lucchitta, Ian P. Skilling, Richard B. Waitt
Topography and Stratigraphy of the Northern Martian Polar Layered Deposits Using Photoclinometry, Stereogrammetry, and MOLA Altimetry
We present two photoclinometric profiles across a trough in the martian northern polar layered terrain. Complications caused by albedo variations were avoided by using an early springtime Viking image with a thin cover of seasonal CO2 frost. The topographic profiles were constrained with stereogrammetric elevations derived from summertime Viking images of the same region.We find that the photoclin
Authors
Lori K. Fenton, Kenneth E. Herkenhoff
Results of the Imager for Mars Pathfinder windsock experiment
The Imager for Mars Pathfinder (IMP) windsock experiment measured wind speeds at three heights within 1.2 m of the Martian surface during Pathfinder landed operations. These wind data allowed direct measurement of near-surface wind profiles on Mars for the first time, including determination of aerodynamic roughness length and wind friction speeds. Winds were light during periods of windsock imagi
Authors
Robert Sullivan, Ronald Greeley, Michael Kraft, Gregory Wilson, Matthew P. Golombek, Kenneth E. Herkenhoff, James Murphy, Peter Smith
Mars south polar spring and summer behavior observed by TES: seasonal cap evolution controlled by frost grain size
Thermal Emission Spectrometer (TES) observations of the recession phase of Mars' south polar cap are used to quantitatively map this recession in both thermal and visual appearance. Geographically nonuniform behavior interior to the cap is characterized by defining several small regions which exemplify the range of behavior. For most of the cap, while temperatures remain near the CO2 frost point,
Authors
Hugh H. Kieffer, Timothy N. Titus, Kevin F. Mullins, Phillip R. Christensen
The state and future of Mars polar science and exploration
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as 3–4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young—preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust
Authors
S.M. Clifford, D. Crisp, D.A. Fisher, Kenneth E. Herkenhoff, S.E. Smrekar, P. C. Thomas, D. D. Wynn-Williams, R.W. Zurek, J.R. Barnes, B.G. Bills, E.W. Blake, W. M. Calvin, J.M. Cameron, M. H. Carr, P. R. Christensen, B. C. Clark, G.D. Clow, J.A. Cutts, D. Dahl-Jensen, W. B. Durham, F. P. Fanale, J.D. Farmer, F. Forget, K. Gotto-Azuma, R. Grard, R.M. Haberle, W. Harrison, R. Harvey, A.D. Howard, A.P. Ingersoll, P.B. James, J.S. Kargel, H. H. Kieffer, J. Larsen, K. Lepper, M. C. Malin, D. J. McCleese, B. Murray, J.F. Nye, D. A. Paige, S.R. Platt, J.J. Plaut, N. Reeh, J.W. Rice, D.E. Smith, C. R. Stoker, K. L. Tanaka, E. Mosley-Thompson, T. Thorsteinsson, S.E. Wood, A. Zent, M.T. Zuber, H.J. Zwally
Surface ages and resurfacing rates of the Polar Layered Deposits on Mars
Interpretation of the polar stratigraphy of Mars in terms of global climate changes is complicated by the significant difference in surface ages between the north and south polar layered terrains inferred from crater statistics. We have reassessed the cratering record in both polar regions using Viking Orbiter and Mariner 9 images. No craters have been found in the north polar layered terrain, but
Authors
Kenneth E. Herkenhoff, Jeffrey J. Plaut