Astrogeology Science Center

Publications

Filter Total Items: 858
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Year Published: 1988

Making a big impression

No abstract available.

Carr, M.H.

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Year Published: 1988

Numerical analysis of Landsat Thematic Mapper images of Antarctica

Landsat-5 Thematic Mapper (TM) data from Dronning [Queen] Maud Land, Antarctica, have been analysed to provide insights into physical properties of the ice sheet. Brightness (at-satellite) temperatures calculated from digital numbers of the thermal band (TM band 6), using state-of-the-art equations and constants (Markham and Barker 1986), are 8°...

Orheim, Olav; Lucchitta, Baerbel K.

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Year Published: 1987

Multispectral Landsat images of Antarctica

No abstract available.

Lucchitta, Baerbel K.; Bowell, Jo-Ann; Edwards, K.L.; Eliason, E.M.; Ferguson, H.M.
Multispectral Landsat images of Antarctica; 1987; B; 1696; Lucchitta, Baerbel K.; Bowell, Jo-Ann; Edwards, K. L.; Eliason, E. M.; Ferguson, H. M.

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Year Published: 1987

The Martian surface

The past four years have been particularly fruitful for Martian research as the enormous volumes of data collected during the Viking mission became readily available to the general science community, and as reformatting of the remote sensing data into cartographic products made the data more useable. The 1:5,000,000‐scale map series is complete,...

Carr, M.H.

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Year Published: 1987

I. Thermal evolution of Ganymede and implications for surface features. II. Magnetohydrodynamic constraints on deep zonal flow in the giant planets. III. A fast finite-element algorithm for two-dimensional photoclinometry

The work is divided into three independent papers: PAPER I: Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the rock component. As...

Kirk, Randolph L.; Stevenson, David J.; Goldreich, Peter M.
Kirk, Randolph Livingstone (1987) I. Thermal evolution of Ganymede and implications for surface features. II. Magnetohydrodynamic constraints on deep zonal flow in the giant planets. III. A fast finite-element algorithm for two-dimensional photoclinometry. Dissertation (Ph.D.), California Institute of Technology.

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Year Published: 1987

Snow and ice studies by thematic mapper and multispectral scanner Landsat images

Digitally enhanced Landsat Thematic Mapper (TM) images of Antarctica reveal snow and ice features to a detail never seen before in satellite images. The six TM reflective spectral bands have a nominal spatial resolution of 30 m, compared to 80 m for the Multispectral Scanner (MSS). TM bands 2–4 are similar to the MSS bands. TM infra-red bands 5...

Orheim, Olav; Lucchitta, Baerbel K.

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Year Published: 1987

Thermal evolution of a differentiated Ganymede and implications for surface features

Thermal evolution models are presented for Ganymede, assuming a mostly differentiated initial state of a water ocean overlying a rock layer. The only heat sources are assumed to be primordial heat (provided by accretion) and the long-lived radiogenic heat sources in the rock component. As Ganymede cools, the ocean thins, and two ice layers develop...

Kirk, Randolph L.; Stevenson, David J.

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Year Published: 1987

Hydromagnetic constraints on deep zonal flows in the giant planets

The observed zonal flows of the giant planets will, if they penetrate below the visible atmosphere, interact significantly with the planetary magnetic field outside the metallized core. The appropriate measure of this interaction is the Chandrasekhar number Q = H^2 /4πρνα^2 λ (H = radial component of the magnetic field, ν = eddy viscosity, λ =...

Kirk, Randolph L.; Stevenson, David J.

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Year Published: 1987

Recent mafic volcanism on Mars

The evidence for volcanism on Mars is commonly accepted, but none has been documented in the Valles Marineris equatorial rift system. A recent survey of the troughs in this valley revealed dark patches that are interpreted to be volcanic vents. The configuration and association of these patches with tectonic structures suggest that they are of...

Lucchitta, Baerbel K.
Recent mafic volcanism on Mars; 1987; Article; Journal; Science; Lucchitta, B. K.

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Year Published: 1987

Valles Marineris, Mars: Wet debris flows and ground ice

Detailed study of the Valles Marineris equatorial troughs suggests that the landslides in that area contained water and probably were gigantic wet debris flows: one landslide complex generated a channel that has several bends and extends for 250 km. Further support for water or ice in debris masses includes rounded flow lobes and transport of some...

Lucchitta, Baerbel K.
Valles Marineris, Mars: Wet debris flows and ground ice; 1987; Article; Journal; Icarus; Lucchitta, B. K.

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Year Published: 1986

Sedimentary deposits in the northern lowland plains, Mars

The lowland plains on Mars have surfaces marked by large polygonal fracture patterns. It was recently proposed that the fracture patterns were developed on sedimentary deposits from outflow channels. We support this hypothesis because of the following observations. (1) Polygonal fracture patterns tend to occur in low areas on Mars that apparently...

Lucchitta, Baerbel K.; Ferguson, H.M.; Summers, C.H.

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Year Published: 1986

Multispectral digital image mapping of Antarctic ice features

Landsat multispectral images of the Antarctic ice sheet have been digitally enhanced by the US Geological Survey to show ice surface features not seen in earlier photographic products of the same scenes. Now for the first time it is worthwhile to prepare image maps at scales of up to 1:250 000 of ice sheet areas even where no nunataks are visible...

Swithinbank, Charles; Lucchitta, Baerbel K.