Magion 4

The characteristic feature of the INTERBALL project is the realization of multi point simultaneous measurements at different altitudes provided by two main satellites together with two subsatellites, each of which is launched into orbit as the passenger of its main satellite.

The main purpose of the subsatellites in the INTERBALL Project is to perform systematic complex studies in the tail polar magnetosphere, magnetosheath and solar wind, of spatial structures of individual space plasma processes, ambient plasma parameters and cause-and-effect relationships by performing measurements synchronized with those made on the main satellite. Measurements at two different points in space for each satellite-subsatellite pair - if their relative positions are known - enable one to distinguish reliably (in one direction, at least) the locations and motions of various plasma structures and/or inhomogeneities in space from the purely time variation of the medium parameters, which is very important for the correct interpretation of experimental results.

The spacecraft of Magion type have been selected as the subsatellites of the Interball project: Magion-4 (C2-X) for the Tail Probe and Magion-5 (C2-A) for the Auroral Probe. The concept of the small subsatellite for the Prognoz-type spacecraft was realized for the first time in this project. Magion-4 was produced in the Czech Republic in collaboration with Russia, Ukraine, Hungary, Austria and has onboard scientific instruments and sensors designed and built in Czech Republic, Russia, Poland, Hungary, Romania, Bulgaria and Slovak Republic. Magion-5 spacecraft is currently being prepared for the launch in 1996 and has onboard scientific insruments from France in addition to the instruments mentioned above.

Principal Technical Characteristics

Selection of scientific payload

As it follows from their main objectives, the measurements made aboard the subsatellites should be adequate to those made aboard the main satellite, as much as it is allowed by the smaller size and weight. Considering everything that has been said above, the following set of scientific payload for the MAGION-4 subsatellite was selected:

List of scientific measurements aboard MAGION-4 subsatellite

  • Magnetic field measurements: 3 axes 0 - 10 Hz.
  • ULF waves: 3 axes, search-coils; 1-10 Hz or 1-30 Hz filters; telemetry: 12 bit ADC; dynamical range 76 dB.
  • ULF/ELF waves: 3 axes search-coils, filterbank (8 channels) 10 Hz - 2 kHz and subcarrier (IRIG) analog telemetry channel.
  • VLF waves: 1 axis, search-coil detector, filterbank (8 channels) in the range 8 Hz - 40 kHz. Spectrum analyzer SAS with 64 frequency steps, 400 Hz - 20 kHz; broad-band analog telemetry channel.
  • Electric fields and waves: 1 axis in the range 0,1 Hz - 400 kHz, set of filters (8 channels). Spectrum analyzer SAS: 64 steps, (1 step - 20 ms), 32 Hz - 2 kHz or 96 steps, 1 - 400 kHz, wide-band analog telemetry (60 kHz max), subcarrier (IRIG) analog telemetry channel.
  • Ion flux fluctuations 1e-12 - 1e-10A, (4sensors, spaced at 120 deg.)
  • Energetic particles - solid-state spectrometer for electrons 20-230 keV and protons 20 keV - 1,3 MeV, 2 directions: antisunward and perpendicular to it.
  • Plasma particles - electrostatic analyzer MPS, electrons and protons 0,2 - 20 keV, axes in the directions of the + and - Z subsatellite axis, i.e. toward the Sun and antisunward, on 16 energy levels.
  • Plasma particles - multidirectional electrostatic analyzer SPS for electrons and protons 0,2 - 20 keV, 16 energy levels.
  • Solar X-ray photometer two energy bands: 10-15 keV, 15-60 keV
  • Two-components current Langmuir probe: 0,3 Hz - 50 kHz