Flying in a tetrahedral (triangular pyramid) formation, the four spacecraft collect the most detailed data yet on small-scale changes in near-Earth space and the interaction between the charged particles of the solar wind and Earth's atmosphere. Cluster II is part of an international collaboration to investigate the physical connection between the Sun and Earth.
			The name Cluster was chosen because of the way the four spacecraft will fly in a group around the Earth. The four individual names (Rumba, Salsa, Samba, Tango) were chosen via a public competition held in all ESA member-states.
	Type		Four identical spacecraft, spin-stabilised (15 rpm)
	Mass		Per spacecraft: 1200 kg, of which 650 kg propellant: and 71 kg scientific payload
	Size		Diameter 2.9 m, Height:1.3 m. Two antenna booms, two 5 m experiment booms and four 50 m experiment wire booms
	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
	WEC		Wave Experiment Consortium ((DWP, EFW, STAFF, WBD, and WHISPER)
	Date		Baikonur, 16 July 2000 and 9 August 2000
	Vehicle		2 Russian Soyuz launchers, each with a Fregat upper stage
			Elliptical polar orbit, 19 000 to 119 000 km, 57 hour period
			European Space Operations Centre (ESOC), Germany.Ground station: Villafranca, Spain