| The Cluster mission, ESA’s
first cornerstone project, together with the SOHO mission, dating back to the
first proposals in 1982, was finally launched in the summer of 2000. On 16 July
and 9 August, respectively, two Russian Soyuz rockets blasted off from the
Russian cosmodrome in Baikonour to deliver two Cluster spacecraft, each into
their proper orbit. By the end of August 2000, the four Cluster satellites had
reached their final tetrahedral constellation. The commissioning of 44
instruments, both individually and as an ensemble of complementary tools, was
completed five months later to ensure the optimal use of their combined
observational potential. On 1 February 2001, the mission was declared
operational.
The main goal of the Cluster mission is to study the
small-scale plasma structures in three dimensions in key plasma regions, such
as the solar wind, bow shock, magnetopause, polar cusps, magnetotail and the
auroral zones. With its unique capabilities of three-dimensional spatial
resolution, Cluster plays a major role in the International Solar Terrestrial
Program (ISTP), where Cluster and the Solar and Heliospheric Observatory (SOHO)
are the European contributions. Cluster’s payload consists of
state-of-the-art plasma instrumentation to measure electric and magnetic fields
from the quasi-static up to high frequencies, and electron and ion distribution
functions from energies of nearly 0 eV to a few MeV. The science operations are
coordinated by the Joint Science Operations Centre (JSOC), at the Rutherford
Appleton Laboratory (UK), and implemented by the European Space Operations
Centre (ESOC), in Darmstadt, Germany. A network of eight national data centres
has been set up for raw data processing, for the production of physical
parameters, and their distribution to end users all over the world. The latest
information on the Cluster mission can be found at http://sci.esa.int/cluster/. |