Citation
Abstract
This article summarizes a study of the accuracy of planetary approach orbit determination based on long, 100-day arcs. Long arc orbit determination is an attractive means for improving the accuracy of radio metric based navigation in situations when conventional, 30-day “short arc” orbit determination strategies are particularly sensitive to bias deep space station (DSS) location errors. The accuracy analysis is based on the Viking Mission A and B trajectories; nevertheless, the results that are presented can be interpreted in a general way. Several error sources which are not usually included in short arc orbit determination analysis have been evaluated in the study, namely, randomly time-varying (stochastic) DSS location errors, Earth-Moon barycenter ephemeris errors, and spacecraft maneuver errors. The stochastic DSS location errors are included to model error effects arising from imperfect calibration of measurement system errors, e.g., troposphere, ionosphere, space plasma, timing, and polar motion. The inclusion of stochastic station errors in the orbit estimation strategies presented proved to be significant; these errors are shown to limit determination of the spacecraft orbit when the bias components of the station location error are also estimated. Example results using the two Viking trajectories nevertheless indicate that long arc radio orbit determination performs favorably in the presence of these and other errors, including conservative station location bias errors.
Details
- Volume
- XVIII
- Published
- December 15, 1973
- Pages
- 57–65
- File Size
- 930.8 KB