Citation
Abstract
Measurements of the round-trip light time (range) from Earth to planetary spacecraft are important for the estimation of the orbits of the planets. The range measurement accuracy is thought to be limited by the calibration of radio signal delays within the Earth tracking antennas. By fitting range measurements to the planetary ephemeris, we find that the average measurement residuals are under 1 m except for measurements from a few tracking stations that show larger systematic effects for several years before 2008. By deleting the small number of measurements that exhibit systematic trends, and estimating a bias for each station, the accuracy of the range measurements is improved by up to 30 percent to a root-mean-square between 55 cm and 80 cm (depending on spacecraft).
Details
- Volume
- 42-190
- Published
- August 15, 2012
- Pages
- 1–11
- File Size
- 1.7 MB