In PDS4 CERTIFIED




                                                  


    Introduction


    The Pioneer Venus multiprobes and orbiter investigated Venus before rigorous archiving was an integral part of a NASA mission. As a result, no systematic archive of raw, calibrated and derived products was preserved. Some data was preserved in NSSDCA and recent (2024) recovery efforts are underway to make the data more accessible. The NSSDCA help page provides an information page and access to a collection of Pioneer Venus data sets. Current efforts (2024) are underway to generate a set of Special Events and to make them available as DPS4 collections.

    The Pioneer Venus Mission consisted of two major parts: the multiprobes and an orbiter. The multiprobes consisted of the carrier or Bus (290 kg); Sounder, a large probe (315 kg) and 3 smaller probes (90 kg each). The probes were launched on August 8, 1978 and reached Venus on December 9, 1978. Sounder was released from the Bus on November 15, 1978, followed by 3 smaller probes on Nov 19, 1978

                              Pioneer Venus Probes and Bus - Atmospheric Entry* All times in UT (= EST + 5 hours) on December 9, 1978
       Large ProbeNorth ProbeDay ProbeNight ProbeBus
    Entry Time (200 km)18:45:3218:49:4018:52:1818:56:1320:21:52
    Impact Time19:39:5319:42:4019:47:5919:52:05*
    Loss of Signal19:39:5319:42:4020:55:3419:52:0720:22:55
    Impact Latitude4.4 N59.3 N31.3 S28.7 S(37.9 S)
    Impact Longitude304.04.8317.056.7(290.9)
    Solar Zenith Angle65.7108.079.9150.760.7
    Local Venus Time7:383:356:460:078:30
    *
    *From NSSDCA collection
    **Bus signal at 110 km altitude
    *** All times in UT (= EST + 5 hours) on December 9, 1978


    See the user’s guide for the description of the data products included in this bundle.

    Large Probe Gas Chromatograph (LGC) Data Collection
    The probe determined the composition of the lower atmosphere of Venus.

    Large Probe Infrared Radiometer (LIR) Data Collection
    The Probe measured the atmosphere thermal flux profile, detected cloud layers and infered their composition, and estimated the atmospheric water vapor content as it descended through the atmosphere.

    Large Probe Solar Flux Radiometer (LSFR) Data Collection
    This radiometer determined the regions in the atmosphere where solar energy was deposited.

    Orbiter Atmospheric Drag (OAD) Observations and Model Data Collection
    The objectives of these observations were (1) to establish the diurnal variation of thermospheric density and density scale height (2) to determine the relationship of solar wind variations to variations in atmospheric density, (3) to determine the relationship of long and short term variation in solar extreme UV radiation to density variations, (4) to search for phenomena such as a semi-annual variation and super rotation of the thermosphere, and (5) to formulate a thermospheric model for the atmosphere of Venus.

    Orbiter Solar Wind Plasma Analyzer (OPA) Data Collection
    The objectives of the plasma analyzer were to measure solar wind conditions (velocity, density, flow direction, and temperature) both outside the Venusian bow shock and inside the magnetosheath flow field, and to study the ionopausal structure.

    Small Probes Net Flux Radiometers (SNFR) Data Collection
    The objectives of the three SNFR instruments were to locate regions of radiative convergence and divergence as a function of altitude and to indicate the height at which solar energy is absorbed by the atmosphere.

    Multiprobes Nephelometer (LN/SN) Data Collection
    The four nephelometer experiments (designated LN on the Large Probe and SN on the Small Probes) measured the energy backscattered from cloud particles.

    Multiprobes Atmospheric Structure (LAS/SAS) Data Collection
    The objective of the four Atmospheric Structure experiments (designated LAS on the Large Probe and SAS on the Small Probes) was to characterize the atmosphere of Venus down to the surface at the four different entry sites.

    Downloading all data files Do we want to do this? Ask Lynn

    Citing Datasets for Publications

    S.A.McLaughlin, Y.-I Won (2024), Pioneer Venus facial Events Data Bundle, NASA Planetary Data System, https://doi.10.17189/m5zf-6f12