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




BE-C (Explorer 27) was a small ionospheric research satellite instrumented with an electrostatic probe, radio beacons, a passive laser tracking reflector, and a Doppler navigation experiment. Its primary objective was to obtain worldwide observations of total electron content between the spacecraft and the earth. The satellite was initially spin stabilized, but it was despun after solar paddle erection. Subsequent stabilization oriented the satellite axis of symmetry with the local magnetic field by means of a strong bar magnet and damping rods. A three-axis magnetometer and sun sensors provided information on the satellite attitude and spin rate. There was no tape recorder aboard so that satellite performance data and electrostatic probe data were observed only when the satellite was within range of a ground telemetry station. Continuous transmitters operated at 162 and 324 MHz to permit precise tracking by "Transit" tracking stations for navigation and geodetic studies. The satellite was turned off on July 20, 1973, due to frequency interference with higher priority spacecraft.

Alternate Names

  • 01328
  • Explorer 27
  • S 66C

Facts in Brief

Launch Date: 1965-04-29
Launch Vehicle: Scout
Launch Site: Wallops Island, United States
Mass: 60.8 kg

Funding Agency

  • NASA-Office of Space Science (United States)


  • Space Physics
  • Earth Science

Additional Information

Questions and comments about this spacecraft can be directed to: Dr. Dieter K. Bilitza



NameRoleOriginal AffiliationE-mail
Mr. Frank T. MartinProject ManagerNASA Goddard Space Flight Center
Mr. Robert E. BourdeauProject ScientistNASA Goddard Space Flight Center
Mr. Larry H. BraceProject ScientistNASA Goddard Space Flight Center
Dr. Robert R. NewtonProject ScientistNASA Goddard Space Flight Center
[] NASA Logo -