Instrument Information
IDENTIFIER urn:nasa:pds:context:instrument:pvo.oad::1.2
NAME Orbiter Atmospheric Drag (OAD) for Pioneer Venus
TYPE Radio Science
DESCRIPTION The Orbiter Atmospheric Drag (OAD) experiment utilized S-band and X-band radio signals from a spacecraft to gather data on the Venusian atmosphere. Its objectives included measuring the diurnal variation of thermospheric density, understanding the impact of solar wind on atmospheric density, examining the effects of solar extreme UV radiation, and investigating phenomena like semi-annual variations and super-rotation. The experiment analyzed Doppler shifts in radio transmissions to calculate spacecraft acceleration and drag coefficients, which, when combined with atmospheric models, helped estimate atmospheric density. The changing periapsis altitude allowed for sampling different atmospheric depths, contributing to studies on atmospheric variations and dynamics.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Keating, G. M., et al., Venus thermosphere and exosphere: First satellite drag measurements of an extraterrestrial atmosphere, Science, 203, No. 4382, 772-774, Feb. 1979.

Keating, G. M., et al., Short-term cyclic variations and diurnal variations of the Venus upper atmosphere, Science, 205, No. 4401, 62-64, July 1979.

Colin, L., Ed., and D. M., Ed. Hunten, Pioneer Venus experiment descriptions, Space Sci. Rev., 20, No. 4, 451-525, June 1977.