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Doppler Tracking Experiment

NSSDCA ID: 1984-128F-04

Mission Name: Vega 2 Balloon
Principal Investigator:Dr. Viktor V. Kerzhanovich


The Vega Balloon Doppler Tracking experiment was designed to measure the drift velocity of the balloons and the turbulence in the Venus' atmosphere. The experiment involved calculating the Doppler shift in the balloon radio signals sent to the Earth. The Doppler shift could then be translated into the velocity of the balloon in the atmosphere along a line between the balloon and Earth after corrections were made for the relative motions of Venus and Earth.

For measurements made while the balloon was near the limb of Venus as seen from Earth the fluctuations were due primarily to changes in the horizontal velocity. When the balloon was near the meridian changes in the vertical velocity were measured, and for points in between a combination of the two motions. The existing radio equipment and master oscillator were used for the experiment. The radio signals were measured on Earth at 0.5 second intervals over periods of 332 seconds which were done every half hour or hour. The accuracy of the measurement was better than 5 cm/sec, limited by the signal to noise ration and the short-term stability of the on-board oscillator.

Alternate Names

  • Vega2Balloon/DopplerTrackingExperiment

Funding Agency

  • Unknown (U.S.S.R)


    Additional Information

    Questions and comments about this experiment can be directed to: Dr. David R. Williams



    NameRoleOriginal AffiliationE-mail
    Dr. Viktor V. KerzhanovichTeam LeaderRussian Academy of

    Selected References

    • Preston, R. A., et al., The VEGA balloon experiment: Initial results from the global radio tracking, Sov. Astron. Lett., 12, No. 1, 10, Jan.-Feb. 1986.
    • Andreev, R. A., et al., Mean zonal winds on Venus from Doppler tracking of the Vega balloons, Sov. Astron. Lett., 12, No. 1, 17, Jan.-Feb. 1986.
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