In PDS3 CERTIFIED
                                                  


    Introduction


    The Pioneer Venus Mission consisted of two major parts: the Multiprobe and the Orbiter. The Multiprobe was composed of the carrier or Bus (290 kg); Sounder, a large probe (315 kg) and 3 smaller probes (90 kg each). It was 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
    *Bus signal at 110 km altitude
    ** Information from NSSDC web site.


    The orbiter carried 16 instruments (total mass 45 kg) to study plasma interaction with the upper atmosphere, make multi-wavelength observations of the clouds and to map the surface with radar. It was launched on May 20,1978 and reached orbit on Dec 4, 1978. Entry into the atmosphere ended the mission on Oct 8, 1992. (See NASA SP-461 by Fimmel, Colin and Burgess for a general review of the mission.)

    Some achievements during the 14 Year mission were
    1. A radar map of the surface at 75 Km resolution
    2. Characterization of Venus’ interaction with the solar wind setting limits on Venus” magnetic field
    3. Established sulfuric acid content of cloud deck
    4. Measured a decline in sulfuric acid in the atmosphere and detected implying active volcanic activity

    References

    The initial descriptions for the mission, its goals and instrumentation is given in
    Space Science Reviews, 20(3), 248-354, 1977a. https://link.springer.com/journal/11214/20/3 and Space Science Reviews, 20(4), 356-525, 1977b. https://link.springer.com/journal/11214/20/4

    Colin, L., Encounter with Venus, Science, 203, No. 4382, 743-745, Feb. 1979.

    An introduction to the JGR special issue covering results is given by Colin, L, The Pioneer Venus Program , Journal of Geophysical Research, VOL. 85, NO. A13, Pages 7575-7598, December 30, 1980, which includes a detailed bibliography.

    Searching for Additional Publications via Author or topic

    Access to Data

    The Pioneer Venus Multiprobe - These data are listed in NSSDCA as Pioneer Venus Special events - Note: This master catalog allows you to search for data set descriptions. Clicking on an entry in the left column gives you a description of the data. Clicking on Coordinated Request and User Support Office located in the right column of that page allows you to order the offline data.

    The Bus made measurements down to 110 km altitude. A region not sampled by the probes. It was equipped with a BNMS - neutral mass spectrometer and a BIMS - ion mass spectrometer.

    Sounder, the large probe was equipped with a parachute and carried seven experiments:
    LMNS - A neutral mass spectrometer to measure the atmospheric composition
    LGC - A gas chromatograph to measure the atmospheric composition
    LSFR - A solar flux radiometer to measure solar flux penetration in the atmosphere
    LIR - An infrared radiometer to measure distribution of infrared radiation
    LCPS - A cloud particle size spectrometer to measure particle size and shape
    LN/SN - A nephelometer to search for cloud particles
    LAS/SAS - Temperature, pressure, and acceleration sensors

    The three smaller identical probes had no parachutes and carried
    LN/SN - A nephelometer
    LAS/SAS - Temperature, pressure, and acceleration sensors
    SNFR - A net flux radiometer experiment to map the distribution of sources and sinks of radiative energy in the atmosphere.
    MWIN - Doppler information was received from all four probes that were targeted for different locations on the planet.


    Pioneer Venus Orbiter - The NSSDCA lists various data sets for ONMS, OAD, OUVS, ORO, OGPE, OTUR, OCPP, OIR, OPA, OMAG, OETP, OIMS, ORPA, OEFD, ORAD, OIDD, OGBD and OCM.
    Note: This master catalog allows you to search for data set descriptions. Clicking on an entry in the left column gives you a description of the data. Clicking on Coordinated Request and User Support Office located in the right column of that page allows you to order the offline data.
    ORSE Orbiter Radio Science Experiment

    POS Spacecraft Position

    ORPA Orbiter Retarding Potential Analyzer

    Composition and Structure of the Atmosphere


    ONMS Orbiter Neutral Mass Spectrometer

    OAD - An atmospheric drag experiment to study the upper atmosphere.

    OUVS - An airglow ultraviolet spectrometer to measure scattered and emitted UV light
    These data are archived in the Atmospheres Node (ATM) pv01_1001, pv01_1002 (Pioneer Venus Orbiter OUVS Inbound Monochrome Images)

    These volumes contain Inbound Monochrome Images (IMIDR) produced from the Orbiter Ultraviolet Spectrometer (OUVS) instrument. Data contained here were obtained between 1978 and 1992. The volume also contains documentation in the form of ancillary files, to support access of the data on these volumes.

    PVO-V-OUVS-5-IMIDR-V1.0

    This data set provides a mission-long set of images at several far-UV and near-UV wavelengths associated with day and night airglow emissions and with reflected sunlight. All Venus phases are sampled, as are all levels of solar activity during 1978-1992.


    ORO - A radio occultation experiment to characterize the atmosphere

    OGPE - A radio science atmospheric and solar wind turbulence experiment.

    OTUR - Radio Occultation Atmospheric Turbulence

    Clouds
    OCPP - A cloud photopolarimeter to measure the vertical distribution of the clouds
    Thermal Balance
    OIR - An infrared radiometer to measure IR emissions from the Venus atmosphere


    Solar Wind and Ionosphere
    OPA - A solar wind plasma analyzer to measure properties of the solar wind.

    OMAG A magnetometer to characterize the magnetic field at Venus.

    OETP An electron temperature probe to study the thermal properties of the ionosphere.

    OIMS An ion mass spectrometer to characterize the ionospheric ion population.

    ORPA - A charged particle retarding potential analyzer to study ionospheric particles.

    OEFD - Orbiter Electric Field Detector


    Surface and Interior
    ORAD - A surface radar mapper to determine topography and surface characteristics

    OIDD - Two radio science experiments to determine the gravity field of Venus.

    High Energy Astronomy
    OGBD - A gamma ray burst detector to record gamma ray burst events.

    OCM - Celestial Mechanics