Abstract
Optical observations of the GEOS satellites were used to obtain orbital solutions with different sets of geopotential coefficients. The solutions were compared before and after modification to high order terms (necessary because of resonance) and then analyzed by comparing subsequent observations with predicted trajectories. The most important source of error in orbit determination and prediction for the GEOS satellites is the effect of resonance found in most published sets of geopotential coefficients. Modifications to the sets yield greatly improved orbits in most cases.
The sets of coefficients analyzed are APL 3.5, NWL5E-6, Köhnlein (1967), Rapp (1967), Kaula (1967), Smithsonian Astrophysical Observatory (SAO)M-1 (1966), SAO AGU (1969), SAO COSPAR (1969) and SAO 1969 Standard Earth. The SAO 1969 models generally give better orbital fits and prediction results than the other models above. However these models can be improved by corrections to resonant coefficients.
The results of these comparisons suggest that with the best optical tracking systems and gravity models, satellite position error due to gravity model uncertainty can reach 50–100 m during a heavily observed 5–6 day orbital arc. If resonant coefficients are estimated, the uncertainty is reduced considerably.
Keywords
Tracking System High Order Term Position Error Model Uncertainty Gravity ModelPreview
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References
- [1]O'Neill, B.: 1968, ‘NONAME An Orbit and Geodetic Parameter Estimation System’, prepared under NASA Contract NAS-5-9756.Google Scholar
- [2]Veis, G.: 1967, ‘The Determination of the Radius of the Earth and Other Geodetic Parameters as Derived from Optical Satellite Data’, paper presented at the XIV General Assembly of the International Union of Geodesy and Geophysics, International Association of Geodesy.Google Scholar
- [3]Lundquist, C. A. and Veis, G.: 1966, Smithsonian Astrophysical Observatory Special Report No. 200, Vol. 1.Google Scholar
- [4]Gaposchkin, E.M.: 1969, ‘Improved Values for the Tesseral Harmonics of the Geopotential and Station Coordinates’, presented at the XII COSPAR Meeting, Prague, May 1969, Smithsonian Institute Astrophysical Observatory.Google Scholar
- [5]Gaposchkin, E. M.: 1969, Provisional Geodetic Parameters, U.S. Gov't Memorandum.Google Scholar
- [6]Guier, W. H. and Newton, R. R.: 1965,J. Geophys. Res. 70.Google Scholar
- [7]Anderle, R. J.: 1965,Geodetic Parameter Set NWL 5E-6 Based on Doppler Satellite Observations, NWL Report 1977.Google Scholar
- [8]Kaula, W. M.: 1966,J. Geophys. Res. 71.Google Scholar
- [9]Köhnlein, W.: ‘The Earth's Gravitational Field as Derived from a Combination of Satellite Data with Gravity Anomalies’, paper prepared for the XIV General Assembly, International Union of Geodesy and Geophysics.Google Scholar
- [10]Rapp, R. H.: 1967, ‘The Geopotential to (14, 14) from a Combination of Satellite and Gravimetric Data’, paper prepared for the XIV General Assembly, International Union of Geodesy and Geophysics.Google Scholar
- [11]Kaula, W. M.: 1966,Theory of Satellite Geodesy, Blaisdell, Waltham, Massachusetts.Google Scholar
- [12]Yionoulis, S. M.: 1968,Improved Coefficients of the Thirteenth-Order Harmonics of the Geopotential Derived from Satellite Doppler Data at Three Different Orbital Inclinations, Johns Hopkins/Applies Physics Laboratory Report TG-1003.Google Scholar
- [13]Douglas, B. C. and Marsh, J.G.: 1970, ‘GEOS-2 and 13th Order Terms of the Geopotential’,Celes. Mech. 1, 479–490.Google Scholar
- [14]Lundquist, C. A.: 1967,Geodetic Satellite Results During 1967, Smithsonian Astrophysical Observatory Special Report 264, December.Google Scholar
- [15]Gaposchkin, E. M. and Lambeck, K.: 1960,1969 Smithsonian Standard Earth, SAO Special Report No. 315.Google Scholar