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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 paper describes the first fixed-baseline polarmetric interferometry, achieved with Jet Propulsion Laboratory's (JPL) TOPSAR radar with co- and cross-polarized signals.
This slide presentation reviews the mask design used for the internal metrology of the Space Interferometry Mission (SIM). Included is information about the project, the method of measurements with SIM, the internal metrology, numerical model of internal metrology, wavefront examples, performance metrics, and mask design
Picometer scale optical metrology specifications for the Space Interferometry Mission require precision calibration functions involving the optical and orientation characteristics of corner cube.
The Space Interferometry Mission (SIM) will be NASA's first dedicated space-based optical interferometer.
This study was undertaken at the Jet Propulsion Laboratory to identify salient features of two competing instrument designs and to select the design that best meets the goals of the Space Interferometry Mission.
Definition and discussion of interference and interferometry
Interferometry of Jupiter in decimeter range
Interferometry methods using scatter plate and plane mirror to test long focus optical systems
Lateral, radial and rotational shearing interferometry
Optical and infrared interferometry will open new vistas for astronomy over the next decade. Space based interferometers, operating unfettered by the Earth's atmosphere, will offer the greatest scientific payoff. They also present the greatest technological challenge: laser metrology systems must perform with sub-nanometer precision; mechanical vibrations must be controlled to nanometers requiring orders of magnitude distrubance rejection; a multitude of actuators and sensors must operate flawlessly and in concert.
This paper discusses the techniques for the reduction of cyclic errors in laser metrology gauges for the space interferometry mission.
The Space Interferometry Mission, planned for launch in 2006, will measure the positions of celestial objects to an unprecedented accuracy of 4x10 to the power of negative six arc (about 1 billionth of a degree).
In this paper, the polarimetric interferometry mode data is calibrated in two steps.
The Space Interferometry Mission is an optical stellar interferometer with a 10 meter baseline capable of micro-arcsecond accuracy astrometry.
The Space Interferometry Mission, slated to launch in 2008, will require simultaneous operation of tens of control loops running at kiloHertz rates. The task of designing a computer control system to run this complex, distributed system will require careful requirements analysis and design flow.
Nulling interferometry is a promising technique for reducing a star's brightness relative to its immediate surroundings, with great potential to enable direct detections of extra-solar planets and zodiacal light.
We summarize here results of our recent study of the relativistic stellar aberration requirements for the Space Interferometry Mission (SIM).
Research and development of techniques of ground-based stellar interferometry have been ongoing at JPL since the late 1980's.