Project MIMOSA

Microsatelite MIMOSA (MIcroaccelerometric Measurement Of Satelite Accelerations) was developed by Space Devices Ltd. for Astronomical Institute of Czech Academy of Sciences. Project coordinator on the side of Astronomical Institute is Mgr. Radek Peresty, who was the head of the workgroup Dynamics of Satelite Motion.
Primary Mission objective of MIMOSA project was measurement of atmospheric drag and other non-gravitional origin forces. In relation with this, the satelite must be of a very regular shape (ideal is sphere), and the major scientific device on board, microaccelerometr MACEK, must be placed in it's center of gravity with a very high precision.
Aboard Mimosa was placed new generation of microaccelerometer, MAC-03.

The Satelite was injected in the orbit in the year 2003 from Russia Pleseck (height 300-1500km, inclination 50-70deg and then activated from ground station in Panska Ves, Czech Republic. There was no orbital maneuvring edvisaged during mission, just attitude control using magnetic subsystem. As a launcher was used Russian rocket SS-19, initially intended for military purposes.
  
   Enlarge MIMOSA

MIMOSA on orbit

Satelite technical data

  • MASS :

    • Total mass at launch :   50kg  ±5kg

  • DIMENSIONS :

    • Dimensions :   560x560x570mm

  • LIFETIME :   18 moths

  • ELECTRICAL POWER :

    • Solar arrays description :
      • GaAs panels 200x200mm, 17 pcs
      • Beginning of life :   20W
      • End of life :   13W
    • Batteries :   Li-Ion, 8Ah

  • TELEMETRY :

    • Antennae :   8+1 antennae
    • Data down line :   56k baud
    • Command up line :   1200 baud
    • Independent technology down line :   1200 baud

  • ORIENTATION AND POSITION :

    • Solar sensors with DSP
    • Magnetometer
    • Attitude control :   3 perpendicular magnetotorquers, actively controlled

  • PROPULSION SUB-SYSTEM :   none

  • CENTER OF GRAVITY BALANCING :

    • Extent :   ±0,6mm
    • Step :   0,001mm

  • CPU :

    • Processor :   SAB80C166
    • ROM :   8kB
    • RAM :   2MB
    • Program can run from ROM or RAM
    • 2 identical CPUs - main and back-up one