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Anderson, J. D.

Publications and source records attributed to Anderson, J. D..

At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

A highly efficient error analysis program for the evaluation of spacecraft tests of general relativity with application to solar probes

A computer program is described which can be used to study the feasibility of conducting relativity experiments on a wide range of hypothetical space missions, and a few applications are presented for solar probes which approach the Sun within 0.25 to 0.35 AU. It is assumed that radio ranging data are available from these spacecraft, and that accuracies on the order of 15 meters can be achieved. This is compatible with current accuracies of ranging to Mariner spacecraft. At this level of accuracy, the range data are sensitive to a number of effects, and for this reason it has been necessary to include a total of up to 23 parameters in the feasibility studies, even though there are only two parameters of real interest in the relativity experiments.

Anderson, J. D.↗
NASA NTRS1972

Testing relativistic gravity theories using radio tracking data from planetary orbiting spacecraft.

We present a thorough analysis of a computational method for determining the numerical values of the relativity and other related dynamical parameters using two-way Doppler and ranging data from planetary orbiting spacecraft. The computational method consists of two parts. From Doppler data we first determine the earth-planet components of the position of the orbiting spacecraft relative to the center of gravity of the planet to high accuracy; adding the observed spacecraft range yields a range value to the center of the planet. These constructed earth-planet range data, referred to as normal points, are then treated as raw data in a regression analysis combined with planetary radar delay and meridian circle measurements to solve for the significant solar system dynamical parameters. The major errors sources in the planetary orbiter process are enumerated and their individual effects on the overall accuracy of the normal point accuracies are presented. The accuracies of the parameter estimates as a function of time, data sampling, and a priori assumptions are illustrated.

Jordan, J. F.↗
NASA NTRS1971

Experimental tests of relativistic gravitation theories

Experimental tests were studied for determining the potential uses of future deep space missions in studies of relativistic gravity. The extensions to the parametrized post-Newtonian framework to take explicit account of the solar system's center of mass relative to the mean rest frame of the Universe is reported. Discoveries reported include the Machian effects of motion relative to the universal rest frame. Summaries of the JPL research are included.

Anderson, J. D.↗
NASA NTRS1971

Radio propagation measurements of the solar corona and gravitational fields: Applications to Mariner 6 and 7

Results from interferometric measurements of the apparent angular deflection of quasi-stellar object are examined. Some preliminary results from Mariner 6 and 7 experiments, particularly from the plasma effect viewpoint, are discussed, along with future experiments and plasma scintillation. Ray bending studies, plasma relativity separation for Mariner 6 and 7, and radio propagation test of general relativity are reviewed. First order approximations and time delay studies are appended, as well as Doppler velocity effect investigations.

Muhleman, D. O.↗
NASA NTRS1971

A measurement of the general relativistic time delay with data from Mariners 6 and 7

The technique for obtaining range measurements is discussed. It involves measuring elapsed time between the transmission of an encoded signal from the ground station and its return from the spacecraft. The theoretical background for the Mariner Mars 1969 relativity test is presented, including computation of orbits and time transformation. Interplanetary and coronal plasma effects on range and Doppler observations at S-band are also considered. The general relativistic propagation delay was measured and a value of 0.997 for the relativity parameter Gamma star was obtained.

Anderson, J. D.↗
NASA NTRS1969

Celestial mechanics

Tracking data analyses of Mariners 6 and 7 for determining Earth Moon mass ratio and Mars mass

Anderson, J. D.↗