ASEPS-0 Testbed Interferometer
The ASEPS-0 Testbed Interferometer is a long-baseline infrared interferometer optimized for high-accuracy narrow-angle astrometry.
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Engineering topics
Gursel, Y.
Publications and source records attributed to Gursel, Y..
Metrology for Spatial Interferometry
The accuracy of the relative metrology gauge developed for the proposed OSI and SONATA missions is improved to sub-picometer level.
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OSI Metrology Gauges
OSI requires a metrology system to measure the three dimensional baseline vector between any two of its siderostats and the distance from the beam combiner to the baseline end points.
Gursel, Y.↗
The outer solar system for 200 million years
A special-purpose computer is used to integrate the orbits of the outer five planets for more than 100 Myr into the future and more than 100 Myr into the past. The strongest features in the Fourier transforms of the orbital elements of the Jovian planets can be identified with the frequencies predicted by linear secular theory. Many of the weaker features in the Fourier spectra are identified as linear combinations of the basic frequencies. Serious differences are noted between the present measurements and the predictions of Bretagnon (1974). The amplitude of the 3.796 Myr period libration of Pluto's longitude of perihelion is modulated with a period of 34 Myr. Very long periods, on the order of 137 Myr, are also seen. The orbit of Pluto is stable for the duration of the integration; the maximum Liapunov characteristic exponent is less than 10 to the -6.8 power/yr.
Applegate, J. H.↗
A digital Orrery
The Orrery, a special computer for high-speed high-precision orbital mechanics computations has been designed and built. On the problems the Orrery was designed to solve, it achieves approximately 10 Mflops in about 1 cu ft of space while consuming 150 W of power. The specialized parallel architecture of the Orrery, which is well matched to orbital mechanics problems, is the key to obtaining such high performance. In this paper the design, construction, and programming of the Orrery is discussed.
Applegate, J. H.↗