Radio Science: Celestial Mechanics (RS)

Description

The purposes of this investigation were to: (1) investigate the high-altitude neutral atmosphere of Jupiter using occultation techniques to measure pressure, temperature, molecular weight, and turbulence; (2) investigate the ionosphere of Jupiter and its interaction with the magnetosphere, using occultation techniques to determine electron number density and plasma scale height; (3) determine the sizes and shapes of the Galilean satellites; (4) search for and characterize atmospheres and ionospheres of the Galilean satellites and study their interactions with the Jovian magnetosphere; (5) determine the structure of the gravitational field of Jupiter from Doppler tracking; (6) determine the masses and gravitational moments of the Galilean satellites and improve knowledge of their orbits; (7) study turbulence, electron density fluctuations, and winds in the Jovian ionosphere; (8) investigate microwave emission from the atmosphere and trapped radiation belts of Jupiter; and, (9) search for VLF gravitational waves incident on the solar system to a level of strain amplitude approximately 1.E-15.

Investigators used the signals transmitted between the Earth and the orbiter and between the probe and the orbiter to carry out their investigations. The Earth-orbiter communications used an S-band (2115 MHz) uplink and transponder to generate a coherent S-X band downlink (2297 MHz and 8422 MHz), using an Earth-oriented 5 m dish antenna. The frequency stability was approximately one part in 1.E+11. The probe-to-orbiter transmission was at a frequency between 1 and 2 GHz, and used a wide-band receiver and body-fixed 1 m dish antenna.

Following the probe mission, this receiver and antenna were to be available to carry out additional investigations.