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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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We conduct an observational search in the 60 mu m COBE DIRBE data for the Kuiper disk, which is predicted to be, at most, a few percent of the brightness of the zoidiacal cloud.
We present a set of general tools to search for multiparameter gravitational-wave signals buried in the noise of a detector.
We have had success using heuristic search techniques able to explore a large space of design options to locate optimal designs within that space.
With adaptive problem solving, we take a biologically-inspired approach to both stochastic optimization and search in order to enable a spacecraft to adapt its environment-specific bevahior in-situ.
One of the primary goals of NASA's Origins program is the search for hospitable planets. I will describe how the Terrestrial Planet Finder (TPF) will revolutionize our understanding of the origin and evolution of planetary systems, and possibly even find signs of life beyond Earth.
One of the primary goals of NASA's Origins program is the search for habitable planets. I will describe how the Terrestrial Planet Finder (TPF) will revolutionize our understanding of the origin and evolution of planetary systems, and possibly even find signs of life beyond the Earth.
In a search for lensed infrared galaxies, ISOCAM images have been obtained toward the rich clusters Abell 2218 and Abell 2219 at 15 micro m.
Two Voyager spacecraft are currently exploring the outer reaches of the heliosphere in search of the termination shock...This paper provides a description of the Voyager Intestellar Mission-...
Ulysses has accumulated five years of interplanetary solar wind plasma and IMF measurements. These data cover from 1 to approximately 5 AU and all the heliographic latitudes. Based on these data, we perform an extensive search for the slow-mode shocks. We find a considerable number of discontinuities that have large magnetic field magnitude changes and also large field normal components.
Doppler tracking of distant spacecraft is the only method currently available for search for gravitational waves in the low-frequency band. Experiments to date and those planned for the near future all involve.
We have searched for radio pulsar companions to 40 nearby OB runaway stars. Observations were made at 474 and 770 MHz with the NRAO 140 ft telescope. The survey was sensitive to long- period pulsars with flux densities of 1 mJy or more. One previously unknown pulsar was discovered, PSRJ2044+4614, while observing towards target O star BD+45,3260. Follow-up timing observations of the pulsar measured its position to high precision, revealing a 9' separation between the pulsar and the target star, unequivocally indicating they are not associated.
We have searched TOPEX/Poseidon sea surface height data for effects from six earthquakes of magnitude >6.1 during 1992-1994 in the western Pacific, including the one near Hokkaido, Japan in July 1993.
The Deep Space Network generates accurate radio science data observables for investigators who use radio links between spacecraft and the Earth to examine small changes in the phase and/or amplitude of the signal to study a wide variety of structures and phenomena in space. Several such studies are directed at aspects of the theory of general relativity such as gravitational redshift and gravitational waves. A gravitational wave is a propagating, polarized gravitational field, a ripple in the curvature of space-time. In Einstein's theory of general relativity, the waves are propagating solutions of the Einstein field equations. Their amplitudes are dimensionless strain amplitudes that change the fractional difference in distance between test masses and the rates at which separated clocks keep time. Predicted by all relativistic theories of gravity, they are extremely weak (the ratio of gravitational forces to electrical forces is about 10(sup -40)) and are generated at detectable levels only by astrophysical sources - very massive sources under violent dynamical conditions. The waves have never been detected but searches in the low-frequency band using Doppler tracking of many spacecraft have been conducted and others are being planned. Upper limits have been placed on the gravitational wave strength with the best sensitivities to date are for periodic waves being 7 x 10(sup -15).
A search for low V Earth-to-Moon trajectories has been initiated. Numerical integration of the equations of motion from the circular restricted three-body problem has resulted in the computation of a trajectory that saves more that 100 m/s over a Hohmann transfer, although the flight time is almost ten months.
This is a brief review of recent plans and current status of the adaptation of an Air Force wide field GEODSS telescope for the discovery and follow-up of Near-Earth Objects (NEOs). The proposed search program will focus on the discovery of natural objects and will proceed on a non-interference basis, i.e. avoiding any impact on GEODSS' dedicated purpose of tracking and monitoring Earth orbiting spacecraft. In September, 1992, JPL representatives had an initial meeting with GEODSS personnel and saw their facilities in Maui where use of GEODSS' telescopes were discussed in terms of using these existing sensors for the detection of NEOs. A result of these meetings was a test run at the GEODSS, Socorro, N. Mexico location to evaluate the tracking and astrometric accuracy of an upcoming close approach of NEA, (4179) Toutatis...
We are conducting a search for supernovae in starburst galaxies at the IRTF. Teh najor difficulty is to reliably detect weak point sources in the presence of a bright and structured background.
We discuss a filtering technique for reducing the two-way Doppler frequency fluctuations of noise sources localized in space that affect the sensitivity of spacecraft Doppler tracking searches for gravitational radiation.
We report on a near-infrared, long-baseline interferometric search for luminous companions to the star 51 Pegasi conducted with the Palomar Testbed Interferometer. Our data is completely consistent with a single-star hypothesis.