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Results for “RADAR ASTRONOMY”

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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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1994

A new presentation of complex voltage data for Goldstone radar astronomy

A presentation method similar to a vector field display or a data-based grid has been used to visualize complex voltage test data taken over multiple subchannels. Unlike simple plots of all data points on the complex plane, the position of the data in the time series is part of the presentation, providing additional information to aid in fault isolation during readiness testing. The 'phase-magnitude' presentation, as it has come to be called, was designed for the demands of real-time data acquisition and processing with remote monitoring over low bandwidth communication links.

Howard, S. D.↗
NASA NTRS1984

Radio Science

Radio science experiments use electromagnetic waves to probe or study the solar system. Three major research areas were identified within this discipline: radio astronomy, radar astronomy, and celestial mechanics. Radio astronomy (or radiometry) is the detection and measurement of naturally produced radio frequency emissions. Sources include surfaces, atmospheres, rings, and plasmas. Radar astronomy is the observation of man-made signals after their interaction with a target. Both imaging and non-imaging results. Celestial mechanics includes all studies related to the motions of (and gravity fields of) bodies within the solar system. These should not be considered rigid separations, but aid in the discussion of the data sets.

Source record↗
NASA NTRS1980

The effects of a satellite power system on ground-based astronomy

The effects of power transmission from the solar power satellite and of radiation from the ground based rectennas on radio astronomy, radar astronomy, and optical astronomy are discussed. Interference sources, acceptable signal and noise levels, and conflicting site requirements for observatories and rectennas are considered.

Thompson, A. R.↗
NASA NTRS1983

New Directions: 1982-2000

The major objective of the Deep Space Network in the period 1983-2000 is the fulfillment of the extremely diverse telecommunications requirements of the known and anticipated users. Deep space exploration projects will continue to occupy a dominant role, although in the mid-1980s, with the completion of the Networks Consolidation Program, high Earth orbiter projects will become substantial users of the Network. Also playing an increasingly important role in the Network of the next decade will be non-flight projects, such as Geodynamics, Radio Astronomy, Radar Astronomy, and the Search for Extraterrestrial Intelligence (SETI). The major challenge in meeting the primary Network objective of the next decade will be that of providing increased performance as required by users at costs which can be borne by NASA in an environment of limited resources. Emphasis will be on increased commonality, flexibility, and automation to reduce maintenance and operations costs, and lower mission costs.

Renzetti, N. A.↗
NASA NTRS1998

Icarus Revisted: Three Decades of Radar Observations of Asteroids

Three decades after the close encounter of 1566 Icarus, which marked the beginning of asteroid radar astronomy, we had a chance to observe the asteroid afresh by using a more developed radar system, and here we present the results of the study.

Icarus asteroid radar astronomy radar cross sectio↗
NASA NTRS1981

Radio Astronomy

The activities of the DSN in support of Radio and Radar Astronomy Operations during September through December 1980 are described. Emphasis is on a report of an experiment selected for use of the DSN by the radio Astronomy Experiment Selection Panel: that of VLBI observations of the energetic galactic object SS-433.

Shaffer, R. D.↗
NASA NTRS1987

Physical properties of asteroids from radar observations

The basic experimental strategies of asteroid radar astronomy are summarized and new information based on recent radar observations about asteroid surface properties is presented. Particular attention is given to the use of radar techniques for constraining asteroid shapes and pole directions. The geometric relationship between a rotating asteroid and its radar echo power spectrum is analyzed.

Ostro, S. J.↗
NASA NTRS1992

Coherent-backscatter effect - A vector formulation accounting for polarization and absorption effects and small or large scatterers

Previous theoretical work on the coherent-backscatter effect in the context of speckle time autocorrelation has gone beyond the diffusion approximation and the assumption of isotropic (point) scatterers. This paper extends the theory to include the effects of polarization and absorption, and to give the angular line shape. The results are expressions for angular variations valid for small and large scatterers and linear and circular polarizations, in lossless or lossy media. Calculations show that multiple anisotropic scattering results in the preservation of incident polarization. Application to a problem in radar astronomy is considered. It is shown that the unusual radar measurements (high reflectivity and polarization ratios) of Jupiter's icy Galilean satellites can be explained by coherent backscatter from anisotropic (forward) scatterers.

Peters, Kenneth J.↗
NASA NTRS1980

Radio astronomy

The activities of the Deep Space Network in support of radio and radar astronomy operations during July and August 1980 are reported. A brief update on the OSS-sponsored planetary radio astronomy experiment is provided. Also included are two updates, one each from Spain and Australia on current host country activities.

Taylor, R. M.↗