International dictionary of geophysics, dynamic satellite geodesy
Application of celestial mechanics to artificial satellite orbit calculations using orbit perturbations
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Application of celestial mechanics to artificial satellite orbit calculations using orbit perturbations
Purposes, principles, accomplishments, and future projects of geodetic satellites
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Resonant satellite orbits for determining geopotential constants
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Potential use of satellites for enhancing positioning capabilities and for marine geodetic control
Kepler data for calculating resonant satellite orbit and gravity constant
Orbit calculations for synchronous geodetic satellites to observe continental drift and Chandler wobble
Visual and photographic tracking of satellites for geodetic and triangulation data
Resonant and nonresonant satellite eccentric orbits for determination of high order terms in geopotential
Verification experiment design for satellite-borne geodetic altimeter operating over seas
Geodetic solution containing resonant geopotential data for synchronous communication satellite orbit determinations
Radar pulse shape and cross section per unit area at vertical incidence from various ocean conditions for use in design of satellite radar altimeter
The design of a drag-free satellite and its application to measuring tidal interaction of the earth and tesseral harmonics are discussed. Principle areas of discussion are: (1) the feasibility of making geophysical measurements which are not possible with conventional satellites, and (2) design of attitude and translation control systems for spinning vehicle and possible coupling of attitude and translation control for gravity stabilized vehicles.
Very-long-baseline interferometry experiments, involving observations of extragalactic radio sources, were performed in 1969 to determine the vector separations between antenna sites in Massachusetts and West Virginia. The 845.130-kilometer baseline was estimated from two separate experiments. The results agreed with each other to within 2 meters in all three components and with a special geodetic survey to within 2 meters in length; the differences in baseline direction as determined by the survey and by interferometry corresponded to discrepancies of about 5 meters. The experiments also yielded positions for nine extragalactic radio sources and allowed the hydrogen maser clocks at the two sites to be synchronized.
Retroreflector packages have been carried to the moon by the Apollo 11, Apollo 14, and Apollo 15 missions, as well as by Luna 17. Laser ranging from the earth onto these packages should eventually yield information on polar motions and crustal movements accurate to a few centimeters, and on UT1 to 100 microsec. Present (1971) error of the range measurements is 30 cm, but accuracy to 3 cm should be obtainable with improvements in methods and equipment.
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