The Cluster concept is to fly four well instrumented space plasma research spacecraft in formation, which will typically be tetrahedral for as long as orbital mechanics permit. Such a formation is uniquely able to provide insights into the three dimensional structure of the space plasma environment on the scale of the spacecraft separation. The spacecraft separation scale will be varied at six monthly intervals throughout the mission, as orbital precession brings the spacecraft through a variety of different areas of Geospace. Although earlier missions have flown two spacecraft together, no previous attempt has been made to use four spacecraft in this way. Challenges include controlling the flotilla of spacecraft and developing instrumentation which makes measurements of sufficient relative accuracy that data from different spacecraft can be reliably compared.

Launches (July and August 2000)

Commissioning (August 2000 to October 2000)

Phase 1 (October 2000 to March 2001)

The spacecraft will form an equilateral tetrahedron (sides of length 600 km) in the region of the Northern Magnetospheric Cusp. The spacecraft will also form such a tetrahedron as they cross the magnetopause in the Southern Hemisphere.

Phase 2 (March 2001 to October 2001)

The spacecraft will form an equilateral tetrahedron (sides of length to be determined, perhaps 6,000 km) in the region of the Magnetotail Central Plasma Sheet. Details to be agreed by Science Working Team.

Phase 3 (October 2001 to March 2002)

The spacecraft will probably form an equilateral tetrahedron (sides of length to be determined) in the region of the Northern Magnetospheric Cusp. Details to be agreed by Science Working Team.

Phase 4 (March 2002 to October 2002)

The spacecraft will probably form an equilateral tetrahedron (sides of length to be determined, perhaps 18,000 km) in the region of the Magnetotail Central Plasma Sheet. Details to be agreed by Science Working Team.

The impact of Cluster II on solar terrestrial physics is likely to be comparable to the effect on astronomy and astrophysics of a telescope which allows one to see a new region of the electromagnetic spectrum for the first time. Cluster II has the potential to show us things that cannot be discovered any other way.
 
 

Return to PEACE Home Page
 

By Andrew Fazakerley
Last updated on27/06/00  by S. Szita