The Galileo Probe Doppler Wind Experiment: Measurement of the deep zonal winds on Jupiter

Abstract

Abstract. During its descent into the upper atmosphere of Jupiter, the Galileo probe transmitted data to the orbiter for 57.5 min. Accurate measurements of the probe radio frequency, driven by an ultrastable oscillator, allowed an accurate time history of the probe motions to be reconstructed. Removal from the probe radio frequency profile of known Doppler contributions, including the orbiter trajectory, the probe descent velocity, and the rotation of Jupiter, left a measurable frequency residual due to Jupiter's zonal winds, and microdynamical motion of the probe from spin, swing under the parachute, atmospheric turbulence, and aerodynamic buffeting. 22,911

Depth of a strong jovian jet from a planetary-scale disturbance driven by storms

“…The power source for these jets (solar radiation, internal heat, or both) and their vertical structure below the upper cloud are major open questions in the atmospheric circulation and meteorology of giant planets [1][2][3] . Several observations 1 and in situ measurements 4 found intense winds at a depth of 24 bar, and have been interpreted as supporting an internal heat source. This issue remains controversial 5 , in part because of effects from the local meteorology 6 .…”

Jupiter’s zonal winds and their variability studied with small-size telescopes

“…However, the details of the global structure of the wind system remained obscure until the Voyager 1 and 2 flybys in 1979, which produced the first set of precise measurements of the zonal winds of Jupiter (Limaye 1986). In 1995, in situ measurements by the Galileo probe (Atkinson et al 1998) and observations from the Galileo orbiter (Vasavada et al 1998) led to new precise measurements of the winds on some localized areas, but did not result in a complete wind profile. Images acquired by the Hubble Space Telescope (HST) were used to obtain several profiles on different dates from 1995 to 2000 (García-Melendo & Sánchez-Lavega 2001).…”

Strong zonal winds from thermal convection in a rotating spherical shell

“…Observations indicate that the ZW on Jupiter extend to significant depths, and are related to atmospheric convection. The Galileo probe measured.wind speeds of 170 m/s down to -o125 km beneath the cloud tops [Atkinson et al, 1998]. Since the surface heat loss is nearly twice that received from solar insolation [Hanel et al, 1981;1983], convective heat transfer is important in the deep atmosphere of each planet [Stevenson, 1982].…”