The Helios experiment on theories of gravitation
Abstract
Experiment 11 of Helios A measuring return time and polarization of an Sband radio signal is described. The experiment deals with the orbit of the spacecraft in the gravitational field of the sun, the planets, and the moon. In first approximation, this orbit is a Keplerian ellipse perturbed by the near planets. In second approximation, further perturbations occur, such as corrections to Newton's theory and the quadrupole moment of an oblate sun. The latter perturbations are the objective of the experiment. Accelerations, due to solar and planetary attraction and repulsion, as well as radiation reactions, are listed.
 Publication:

Helios Satellite Sci. Data Evaluation
 Pub Date:
 October 1974
 Bibcode:
 1974hsde.rept...15K
 Keywords:

 Gravitation Theory;
 Helios A;
 Orbit Perturbation;
 Spacecraft Orbits;
 Acceleration (Physics);
 Gravitational Effects;
 Radiation Pressure;
 Radio Signals;
 Solar Radiation;
 Spacecraft Tracking;
 Theorem Proving;
 Transit Time;
 Ultrahigh Frequencies;
 Astrodynamics