Determination of the System Mass and the Individual Masses of Pluto and Charon from New Horizons Radio Tracking
Abstract
One objective of the New Horizons Radio Science Experiment REX is the direct determination of the system mass and the individual masses of Pluto and Charon. About four weeks of two-way radio tracking centered around the closest approach of New Horizons to the Pluto system were processed. Major problems during the processing were the changes in spacecraft attitude by thrusters which applied extra Δv to the spacecraft motion masking partially the continuously perturbed motion caused by the attracting forces of the Pluto system members. The times of the spacecraft thruster activity are known but the applied Δv magnitude needed to be specifically adjusted. No two-way tracking was available during the flyby day on 14th July but slots of the REX one-way uplink observations cover the most important time near closest approach, these are for example the Pluto and Charon Earth occultation entries and exits. The REX data during the flyby day allowed to extract the individual masses of Pluto and Charon from the system mass at high precision. The relative errors of the mass determinations are below 0.02% and 0.2%, respectively. The masses of the 4 small satellites in the Pluto system could not be resolved.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.P51B2134H
- Keywords:
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- 6099 General or miscellaneous;
- PLANETARY SCIENCES: COMETS AND SMALL BODIESDE: 6218 Jovian satellites;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTSDE: 6299 General or miscellaneous;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTSDE: 5499 General or miscellaneous;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS