Publications
Filter Total Items: 915
TES premapping data: Slab ice and snow flurries in the Martian north polar night
In the 1970s, Mariner and Viking spacecraft observations of the north polar region of Mars revealed polar brightness temperatures that were significantly below the expected kinetic temperatures for CO2 sublimation. For the past few decades, the scientific community has speculated as to the nature of these Martian polar cold spots. Thermal Emission Spectrometer (TES) thermal spectral data have show
Authors
Timothy N. Titus, Hugh H. Kieffer, Kevin F. Mullins, Phillip R. Christensen
TES mapping of Mars' north seasonal cap
The Mars Global Surveyor thermal emission spectrometer has made observations of Mars' north polar region for nearly a full martian year. Measurements of bolometric emission and reflectance, as well as brightness temperatures in specific bands synthesized from thermal radiance spectra, are used to track the behavior of surface and atmospheric temperatures, the distribution of condensed CO2 and H2O,
Authors
Hugh H. Kieffer, Timothy N. Titus
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
Antarctic ice streams and outflow channels on Mars
New sonar images of the Antarctic sea floor reveal mega-scale glacial lineations that are strikingly similar to longitudinal flutes in martian outflow channels. The analogs suggest that ice moved through the martian channels in places and carved the flutes. The ice in martian channels may have moved like Antarctic ice streams on deformable debris saturated with water under high pore pressure. On M
Authors
Baerbel K. Lucchitta
The roughness of natural terrain: A planetary and remote sensing perspective
We examine the various methods and parameters in common use for quantifying and reporting surface topographic "roughness." It is shown that scale-dependent roughness parameters are almost always required, though not widely used. We suggest a method of standardizing the parameters that are computed and reported so that topographic data gathered by different workers using different field techniques
Authors
Michael K. Shepard, Bruce A. Campbell, Mark H. Bulmer, Lisa R. Gaddis, Tom G. Farr, Jeffrey J. Plaut
Abstracts of the Annual planetary geologic mappers meeting; June 22-24, 2000, Flagstaff, Arizona
No abstract available.
Authors
Kenneth L. Tanaka, Derrick D. Hirsch
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