Official name CLUSTER II-FM8
Alternative name Tango (Cluster 2/FM8)
Cospar ID 2000-045B
Norad ID 26464
Launch date 2000-08-09
Launch site TTMTR
Launch vehicle Soyuz-U Fregat
Country/Organization Europe
Type application Magnetospheric Research
Operator ESA
RCS size LARGE
Decay date ON ORBIT
Period (min) 3256.51
Inclination (deg) 138.91
Perigee (km) 12609
Apogee (km) 120189
Eccentricity 0.810102561785569
Mean motion (revs. per day) 0.44219118012842
Semi-Major axis (km) 72777.135
Raan (deg) 357.5857
Arg of perigee (deg) 212.5014
Shape Cyl + 4 Ant
Mass (kg) 1186
Diameter (m) 2.9
Height (m) 1.3
Span (m^2) 100
Contractors Dornier (#1 - 4), Astrium (#5 - 8)
Equipment FGM, EDI, ASPOC, STAFF, EFW, DWP, WHISPER, WBD, PEACE, CIS, RAPID
Propulsion S400 engine
Configuration Cylinder, spin stabilized
Power Solar cells, batteries

Cluster is an magnetospheric research project, consisting of a constellation of four identical satellites. Part of the first Cornerstone Mission in the European Space Agency's long-term space science programme, the Cluster II satellites were built to replace the original Cluster mission, which was aborted after Ariane-5G's maiden flight in June 1996 failed to launch the satellites. The mission's objective is to research the Earth's magnetosphere and its interaction with the solar winds, via four identical satellites flying in formation which take simultaneous measurements to provide the most detailed three-dimensional study of changes and processes taking place in near-Earth space. The four satellites were launched in 2000 on two Soyuz-U Fregat rockets.

Astrium was lead industrial contractor for the development and manufacture of the Cluster II satellites, heading a team of European aerospace indsutry partners from 14 European countries.

Each satellite features 11 instruments:

  • FGM: Fluxgate Magnetometer
  • EDI: Electron Drift Instrument
  • ASPOC: Active Spacecraft Potential Control experiment
  • STAFF: Spatio-Temporal Analysis of Field Fluctuation experiment
  • EFW: Electric Field and Wave experiment
  • DWP: Digital Wave Processing experiment
  • WHISPER: Waves of High frequency and Sounder for Probing of Electron density by Relaxation experiment
  • WBD: Wide Band Data instrument
  • PEACE: Plasma Electron And Current Experiment
  • CIS: Cluster Ion Spectrometry experiment
  • RAPID: Research with Adaptive Particle Imaging Detectors

The Cluster scientific mission is extended until September 2024, when one of the four satellites will re-enter the Earth atmosphere. Two years of post-operations and monitoring of the spacecraft will follow, until re-entry of the last spacecraft in September 2026.

Satellite COSPAR Date LS Launch Vehicle Remarks
CLUSTER II-FM7 2000-041A 2000-07-16 TTMTR Soyuz-U Fregat with Cluster FM7
CLUSTER II-FM6 2000-041B 2000-07-16 TTMTR Soyuz-U Fregat with Cluster FM6
CLUSTER II-FM5 2000-045A 2000-08-09 TTMTR Soyuz-U Fregat with Cluster FM8
CLUSTER II-FM8 2000-045B 2000-08-09 TTMTR Soyuz-U Fregat with Cluster FM5