NASA Logo, National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive Header

Langmuir Probe

NSSDCA ID: 1967-042A-01

Mission Name: Ariel 3
Principal Investigator:Prof. J. Sayers


Electron temperatures were determined by employing an extension of the Langmuir probe technique. Two identical rhodium-plated spherical probes, 3.2 cm in diameter and with a 6.4-cm center-to-center distance, were linearly swept from -6.0 to +6.0 V in 5.2 s. This sweep voltage was modulated by a low-level sine wave signal of 6.0 kHz. The two probes, however, were kept at slightly different potentials with respect to the spacecraft. The differential currents to each probe were compared, and automatically kept in a fixed ratio by adjustment of this voltage difference between the two probes. Under these conditions, the electron temperature was a function of this known ratio and the value of the voltage difference as the probes were swept through the retarding region. The experiment was operated for 5.2 s and then turned off for the same amount of time while the electron density experiment was turned on. The experiment operated normally, and useful data were obtained. A more detailed explanation of the experiment can be found in J. H. Wagner, "University of Birmingham electron density and temperature experiments on the satellite Ariel 3," Radio and Electronic Engineer, v. 35, n. 1, pp. 55-63, January 1968.

Alternate Names

  • Ariel3/LangmuirProbe
  • Electron Density and Temperature


  • Space Physics: Ionospheric Studies

Additional Information

Questions and comments about this experiment can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Miss B. T. LoftusGeneral ContactUniversity of Birmingham
Prof. J. SayersPrincipal InvestigatorUniversity of Birmingham
[] NASA Logo -