Engineering topics
Publications and source records attributed to Smythe, W. D..
NIMS results from the 2001 Galileo fly-bys of Io will be presented, focusing on three calderas that may contain lava lakes. Preliminary results from the January 2002 Io fly-by will be presented. Additional information is contained in the original extended abstract.
Laboratory measurements of the reflectance phase curve, a measurement of great importance in understanding the texture of planetary regoliths, are not consistent with widely accepted theoretical models. Additional information is contained in the original extended abstract.
The thermal output of Io is mapped using all nighttime observations obtained by Galileo NIMS. Additional information is contained in the original extended abstract.
This paper will discuss observations from the 2001 fly-bys of Io and present preliminary results from the last Galileo Io fly-by.
Explore the source record for details and available documents.
Particles in a planetary regolith can be treated as independent scatterers when their size is large compared with the wavelength of light. The nature of this scattering, however, is poorly understood as the particle size approaches and becomes smaller than the wavelength. In order to understand this interaction better, the reflectances of well-sorted particulate samples of known composition were measured. This reflectance data was then analyzed to determine how scattering properties change with particle size.
The MARSES is the sounding instrument developed of searching for groundwater, water-ice or permafrost layers existing in some depth under the visible surface in the dry lands of Mars. One of the more important challenges facing natural resource managers today is how to identify, measure and monitoring the cumulative impacts of land use decisions across space and time. The secondary task is to measure the soil properties of Martian subsurface, which includes porosity, electrical resistance of the liquid phase, thermal conductivity, temperature dependence. A main task of the MARSES monitoring system is to examine changes in the subsurface properties of local areas regolith on the Martian surface on the base of the database of various soil slices in terrestrial conditions
The Near-Infrared Mapping Spectrometer on Galileo has observed Io since June 1996. In 1999 and 2000, the spacecraft made three close fly-bys to Io, revealing for the first time, the detailed thermal structure of some of Io's hot spots.
Io remains one of the most fascinating objects in the solar system: the only place beyond Earth where we can watch hard-rock geology in action. In its high heat flow Io resembles the early Earth, providing a present-day analog to some of the processes that dominated the Earth's geology at the time that life first appeared. Io's usefulness as an early-Earth analog has been underscored recently by the detection of very high eruption temperatures, hotter than terrestrial basaltic lavas. These temperatures are most plausibly interpreted as resulting from ultramafic lava compositions, analagous to the komatiites that were common on Earth in the Precambrian but which have been virtually absent during the Phanerozoic. The large scale of many Io eruptions also provides useful analogs to Phanerozoic terrestrial eruptions, such as flood basalts, which are important for the Earth's geological and biological evolution but which occur too rarely to be witnessed by humans on our own planet. By providing living examples, Io can thus play the same role in understanding large-scale planetary volcanism that volcanically active terrestrial regions have played in understanding the results of smaller-scale volcanic processes seen in the geological record worldwide. Additional information is contained in the original extended abstract.
Cometary nuclei are the most primitive bodies in the solar system, containing a cosmo-chemical record of the primordial solar nebula. Flyby missions to comets, such as those that encountered Comet Halley in 1986, provide a glimpse at this record. However, to study a cometary nucleus in detail requires a rendezvous mission, i.e., a nucleus orbiter. Only an orbiter provides the ability to map the entire nucleus surface at high resolution, to study the complex chemistry in the cometary coma and its variation with time, and to determine the mass and bulk density of the nucleus, key parameters in understanding how small bodies first formed in the solar nebula. A nucleus orbiter also provides the opportunity to sense the nucleus surface in preparation for more ambitious landing and sample return missions in the future. Additional information is contained in the original extended abstract.
This spectral study of Io identifies the infrared components of the visible spectral units (green and dark) as identified by Galileo. The green units possess sulfur dioxide and the dark units are associated with infrared thermal signatures. Additional information is contained in the original extended abstract.
Observations by Galileo's Near-Infrared Mapping Spectrometer were used to map the thermal structure of several of Io's hot spots, revealing different styles of volcanism Additional information is contained in the original extended abstract..
Near Infrared Mapping Spectrometer data acquired during the I24, 25, and 27 Io's Fly-bys by Galileo are analyzed to map the SO2 frost abundance and granularity. This allows a better understanding of the dynamics and evolution of gas condensation around volcanic plumes. Additional information is contained in the original extended abstract.
The laboratory investigation of the scattering properties of candidate planetary regolith materials is an important technique for understanding the physical properties of a planetary regolith. Additional information is contained in the original extended abstract.
Models of Io's plumes have been run varying atmospheric pressure, vent size, and volatile content. These simulations suggest that eruptions with low volatile content can form pyroclastic flows on Io. Additional information is contained in the original extended abstract.
There are new findings on Io regarding its volcanic status.
Explore the source record for details and available documents.