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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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This research using JERS-1 SAR data has been very fruitful, resulting in a strong collaboration with geodesists and geophysicists in Japan, and several important papers characterizing crustal deformation, and the capabilities and limitations of JERS data for these studies.
Interferometric RADARSAT data are used to map ice motion in the source areas of four West Antarctic ice streams.
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The NASA/JPL AIRSAR system was upgraded to collect polarimetric interferometric data from the June 98 deployment.
Deep nulling of both laser and thermal radiation has been demonstrated in the laboratory at visible wavelengths, by means of a rotational shearing interferometer (RSI) coupled to single-mode input and output fibers.
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This paper presents an adaptive control system for coordination and control of a fleet of micro-spacecraft moving in formation.
Fifteen synthetic-aperture radar (SAR) images of the Ronne Ice Shelf, Antarctica, obtained by the European Space Agency (ESA)'s Earth Remote Sensing satellites (ERS) 1 & 2 are used to study ice-shelf dynamics near two ends of the iceberg-calving front.
We compare Earth Remote Sensing (ERS) satellite synthetic-aperture radar (SAR) interferograms with artificial interferograms constructed using output of a finite-element ice-shelf flow model to study the dynamics of Filchner-Ronne Ice Shelf (FRIS) near Hemmen Ice Rise (HIR) where the iceberg-calving front itersects Berkener Island (BI).
Comparison between numerical model ice-shelf flow simulations and synthetic aperture radar (SAR) interferograms is used to study the dynamics at the Hemmen Ice Rise (HIR) and Lassiter Coast (LC) corners of the iceberg-calving front of the Filchner-Ronne Ice Shelf (FRIS).
High-resolution radar images of Moreno Glaciar, Argentina, acquired by the Shuttle Imaging Radar C (SIR-C) on October 9 and 10 1994, at 24-cm wavelength (L-band), are utilized to map the glacier velocity both interferometrically and using a novel feature tracking technique.
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Synthetic aperture radar has been used for high resolution imaging from aircraft and satellites for many years.
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We have developed a technique that allows SIM to measure relative stellar positions with an accuracy of 1 micro-arcsecond at any time during its 5-yr mission. Unlike SIM's standard narrow-angle approach, Gridless Narrow Angle Astrometry (GNAA) does not rely on the global reference frame of grid stars that reaches full accuracy after 5 years. GNAA is simply the application of traditional single-telescope narrow angle techniques to SIM's narrow angle optical path delay measurements. In GNAA, a set of reference stars and a target star are observed at several baseline orientations. A linearized model uses delay measurements to solve for star positions and baseline orientations. A conformal transformation maps observations at different epochs to a common reference frame. The technique works on short period signals (P=days to months), allowing it to be applied to many of the known extra-solar planets, intriguing radio/X- ray binaries, and other periodic sources. The technique's accuracy is limited in the long-term by false acceleration due to a combination of reference star and target star proper motion. The science capability 1 micro-arcsecond astrometric precision - is unique to SIM.