Astrogeology Science Center

Publications

Filter Total Items: 890
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Year Published: 2001

Mars exploration

An international flotilla of spacecraft are to be sent to Mars over the next decade in an effort to understand the planet's geology and climate history, and to determine whether some form of life ever started there. At least two spacecraft will be sent at each launch opportunity, and at times up to four spacecraft may be operating simultaneously...

Carr, M.H.; Garvin, James B.

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Year Published: 2001

Geologic Map of the Lavinia Planitia Quadrangle (V-55), Venus

Introduction The Lavinia Planitia quadrangle (V-55) is in the southern hemisphere of Venus and extends from 25 to 50 south latitude and from 330 to 360 longitude. It covers the central and northern part of Lavinia Planitia and parts of its margins. Lavinia Planitia consists of a centralized, deformed lowland flooded by volcanic deposits and...

Ivanov, Mikhail A.; Head, James W.
Geologic Map of the Lavinia Planitia Quadrangle (V-55), Venus; 2001; I; 2684; Ivanov, Mikhail A.; Head, James W., III

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Year Published: 2001

Geologic Map of the MTM-85000 Quadrangle, Planum Australe Region of Mars

Introduction The polar deposits on Mars probably record martian climate history over the last 107 to 109 years (for example, Thomas and others, 1992). The area shown on this map includes layered polar deposits and residual polar ice, as well as some exposures of older terrain. Howard and others (1982) noted that an area (at lat 84.8 S., long...

Herkenhoff, Kenneth E.

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Year Published: 2001

Geologic Maps of the Dardanus Sulcus (Jg-6), Misharu (Jg-10), Nabu (Jg-11), and Namtar (Jg-14) Quadrangles of Ganymede

Ganymede is the largest (~5,200 km diameter) of the Jovian satellites. Surficial features on Ganymede, as recorded by the Voyager 1 and 2 spacecraft (Smith and others, 1979a; 1979b), indicate a complex history of crustal formation. Several episodes of crustal modification led to the formation of curvilinear systems of furrows in dark terrain, the...

Maxwell, Ted A.; Marvin, Ursula B.
Geologic Maps of the Dardanus Sulcus (Jg-6), Misharu (Jg-10), Nabu (Jg-11), and Namtar (Jg-14) Quadrangles of Ganymede; 2001; I; 2642; Maxwell, Ted A.; Marvin, Ursula B.

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Year Published: 2001

Utilizing Mars Digital Image Model (MDIM) and Mars Orbiter laser Altimeter (MOLA) data for photogrammetric control

The USGS is producing digital elevation models (DEM) and topographic maps of Mars at scales of 1:250,000 to 1:1,000,000. The initial source material will be Viking Orbiter images, with a later transition to Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) when stereo coverage from that source is available for topographic mapping. The digital...

Rosiek, Mark R.; Kirk, Randolph L.; Hare, Trent M.; Howington-Kraus, Elpitha

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Year Published: 2001

Planetary geodesy and cartography at the USGS, Flagstaff: Moon, Mars, Venus, and beyond

An important theme of our work is the synergistic use of a variety of geodetic, cartographic, and photogrammetric software packages. The USGS digital cartographic software system ISIS provides most of the processing capability needed for planimetric mapping tasks such as our revision of the global digital image mosaic of Mars (MDIM).  The...

Kirk, Randolph L.; Rosiek, Mark R.; Howington-Kraus, Elpitha; Eliason, Eric M.; Archinal, Brent A.; Lee, Ella M.

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Year Published: 2001

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...

Lucchitta, Baerbel K.
Antarctic ice streams and outflow channels on Mars; 2001; Article; Journal; Geophysical Research Letters; Lucchitta, B. K.

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Year Published: 2001

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...

Murray, B.; Koutnik, M.; Byrne, S.; Soderblom, Laurence A.; Herkenhoff, Kenneth E.; Tanaka, K.L.

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Year Published: 2001

Rock types of South Pole-Aitken basin and extent of basaltic volcanism

The enormous pre-Nectarian South Pole-Aitken (SPA) basin represents a geophysically and compositionally unique region on the Moon. We present and analyze the mineralogical diversity across this basin and discuss the implications for basin evolution. Rock types are derived from Clementine multispectral data based on diagnostic characteristics of...

Pieters, Carle M.; Head, James W.; Gaddis, Lisa R.; Jolliff, B.; Duke, M.

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Year Published: 2001

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...

Kieffer, Hugh H.; Titus, Timothy N.

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Year Published: 2001

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...

Titus, Timothy N.; Kieffer, Hugh H.; Mullins, Kevin F.; Christensen, Phillip R.

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Year Published: 2001

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...

Shepard, Michael K.; Campbell, Bruce A.; Bulmer, Mark H.; Gaddis, Lisa R.; Farr, Tom G.; Plaut, Jeffrey J.