Instrument Information
IDENTIFIER urn:nasa:pds:context:instrument:pvo.oetp::2.2
NAME Electron Temperature Probe (OETP) for Pioneer Venus
TYPE Langmuir Probe
DESCRIPTION The Pioneer Venus Orbiter Electron Temperature Probe (OETP) is an instrument designed for in-situ measurements of electron temperature and plasma density in Venus' ionosphere. Utilizing cylindrical Langmuir probes, the OETP features adaptive voltage circuitry that continuously adjusts to changing conditions, enabling the collection of high-resolution data despite limited telemetry rates. The system includes independent amplifiers for each probe, adaptive sweep voltage circuits, and onboard data storage, facilitating the transmission of key ionospheric parameters to Earth. The probe has completed over 250 successful passes through Venus' nightside ionosphere, demonstrating robust performance in capturing crucial plasma characteristics.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Brace, L.H., 'Global Structure of Ionosphere Temperature', in Space Research X. Amsterdam, The Netherlands: North-Holland, p.633, 1970.

Brace, L.H., 'Orbiter Electron Temperature Probe', L. Colin and D.M. Hunten, Eds. Space Sci. Rev., Vol.20, No.4, p.454, June 1977.

Brace, L.H., R.F. Theis, and A. Dalgarno, 'The Cylindrical Electrostatic Probes for Atmosphere Explorer -C, -D, -E', Science, Vol.8, No.4, p.341, Apr.1973.

Brace, L.H., R.F. Theis, J.P. Krehbiel, A.F. Nagy, T.M. Donahue, M.E. McElroy, and A. Pedersen, 'Electron Temperatures and Densities in the Venus Ionosphere', Science, Vol.203, p.763, Feb.23, 1979.

Brace, L.H., H.A. Taylor Jr., P.A. Cloutier, R.E. Daniell Jr., and A.F. Nagy, 'On the Configuration of the Nightside Venus Ionopause', Geophys. Res. Lett., Vol.6, p.345, 1979.

Brace, L.H., R.F. Theis, H.B. Niemann, H.G. Mayr, W.R. Hoegy, and A.F. Nagy, 'Empirical Models of the Electron Temperature and Density in the Nightside Venus Ionosphere', Science, Vol.205, p.102, 1979.

Hoegy, W.R., and L.E. Wharton, 'Current to Moving Spherical and Cylindrical Electrostatic Probes', J. Appl. Phys., Vol.44, No.12, p.5365-5371, 1973.

Krehbiel, J.P., L.H. Brace, J.R. Cutler, W.H. Pinkus, and R.B. Kaplan, 'Pioneer Venus Orbiter Electron Temperature Probe', IEEE Transactions on Geoscience and Remote Sensing, GE-18, 49, 1980.

Langmuir, I. and H. Mott-Smith, Jr., 'Studies of the Electric Discharges in Gases at Low Pressures', Gen. Elec. Rev., p.616, Sept.1924.

Mott-Smith, H. and I. Langmuir, 'The Theory of Collectors in Gaseous Discharges', Phys. Rev., Vol.28, pp.727-763, 1926.

Shai, M.C., 'Formulation of Electrically Conductive Thermal-Control Coatings ', NASA Tech. Paper 1218, Apr.1978.

Smith, D., 'The Application of Langmuir Probes to the Measurement of Very Low Electron Temperatures', Planet. Space Sci., Vol.20, p.1721, 1972.

Spencer, N.W., L.H. Brace, G.R. Carignan, D.R. Taeusch, and H.B. Niemann, 'Electron and Molecular Nitrogen Temperature and Density in the Thermosphere', J. Geophys. Res., Vol.70, pp.2665-2698, 1965.

Yang, L., 'Preparation and Evaluation of CVD Rhenium Thermionic Emitters', in The Third Annual Conference on Chemical Vapor Deposition, F.A. Glaski, Ed., American Nuclear Society, 1972.