Dong Fang Hong 39

Launch data: Designation 23009 / 94010B Launch date 08 Feb 1994 Launch site  Xichang, LC-2 Launch vehicle  CZ-3A Mission Simulated satellite Geosynchronous Transfer Earth orbit: Perigee / Apogee  210 x 36125 km Eccentricity   Inclination  28.6 deg Period  570.03 min

Artist's view of the SJ-4 spacecraft in orbit (image credit: CAST)

Spacecraft data:

Sensor complement:

• Three instruments were designed for the space radiation environment and radiation effect test project, including a satellite surface potentiometer and two single particle effect testers (one single particle static monitor and one single particle dynamic monitor). The instruments are:
  • EED (High Energy Electron Detector)
  • EPS (High Energetic Proton and heavy ion Detector)
  • ESA (Electrostatic Analyzer)
  • SPM (Surface Potential Monitor)
  • SEUM (SRAM Single Event Upset Monitor)
  • SEEM (Dynamic Single Event Effect Monitor).
• The plasma detector of the ESA (Electrostatic Analyzer) instrument was the first of China with the objective to detect the hot plasma which causes the high potentials on a spacecraft surface (energy range of 100 eV to 40 keV). - SJ-4 operated for about half a year and yielded a lot of science data.

Photo of the SJ-4 payload (image credit: CNSA)

Mission details:

• SJ-4 is a magnetospheric mission (particles and fields research). The objective was to monitor the space radiation environment and its effects in an elliptical orbit. The S/C, built by CAST, has a mass of 397 kg with dimensions: 1.6 m diameter and 2.1 m in height.