Skip to main content
SearchLoginLogin or Signup

Reprocessing Pioneer Venus Orbiter Radio Occultation Data

Presentation #502.08 in the session Venus I (Oral Presentation)

Published onOct 23, 2023
Reprocessing Pioneer Venus Orbiter Radio Occultation Data

RIU-Planetary Research has won funding support for the reprocessing and the interpretation of the original raw open-loop occultation data taken by the Pioneer Venus Orbiter radio science experiment ORO from 1979 to 1988. These original raw open-loop data are available from the PDS while original processed atmospheric and ionospheric (temperature and electron density, respectively) profiles from the Venus atmosphere are not.

We apply modern software code together with a new version of the Venus gravity field and newly processed orbit data available as SPICE kernels.

A review of the original open-loop data sets showed a variety of observation lengths ranging from a few minutes to about 20 minutes duration. The longer observation sets contain ingress (at two-way) and egress (at one-way) data. The uplink was performed at S-band, the downlink at coherent dual-frequency S-band and X-band. The X-band downlink was switched-on shortly before going into occultation, so that a relatively short baseline exists. The received signal power data at S-band is of very good quality, the received X-band signal power data shows a modulation by the spacecraft spin period due to the much narrower beam.

We shall present atmospheric and ionospheric profiles derived from S-band and differential Doppler recordings, respectively, processed from exemplary original Pioneer Venus Orbiter raw open-loop data sets and compare them with VEX VeRa radio occultation profiles for comparable observation conditions.

No comments here