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




This mission was part of the Japanese contribution to the International Magnetospheric Study, and it carried out coordinated observations with Kyokko. Investigations of correlated mechanisms between particles and fields and plasma turbulence were made with in situ measurement techniques using electrostatic particle analyzers. The spacecraft, a 12-sided polyhedron, carried extendable dipole antennas with lengths of 103 m and 69.6 m, and a 1-m boom for a vector magnetometer. A solar panel array provided 30 W into a battery and regulator system. The spacecraft spin stabilized at 150 rpm but dropped to 3 rpm when the two sets of antennas were extended. Attitude was measured with a sun sensor to an accuracy of 0.5 deg. A 0.5-w 136-MHz PCM/PM telemetry system handled 256 or 1024 bps, and a 2-w 400-MHz PM system handled wideband 10-kHz or 3-kHz data. Data acquisition was in real time except for a 10-Kbyte memory for housekeeping and plasma parameter data.

Alternate Names

  • 11027
  • EXOS-B

Facts in Brief

Launch Date: 1978-09-16
Launch Vehicle: M-3H
Launch Site: Uchinoura Space Center, Japan
Mass: 92 kg
Nominal Power: 30 W

Funding Agency

  • Institute of Space and Aeronautical Science, U of Tokyo (Japan)


  • Space Physics

Additional Information

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



NameRoleOriginal AffiliationE-mail
Prof. Hiroshi OyaProject ScientistUniversity of
Prof. Tatsuzo ObayashiProject ManagerInstitute of Space and Aeronautical Science
Dr. Atsuhiro NishidaProject ScientistInstitute of Space and Aeronautical
Dr. Nobuki KawashimaProject ScientistInstitute of Space and Aeronautical
[] NASA Logo -