Ready to fly: unusual view of Cluster launcher
The nose (or fairing) of the Soyuz launch vehicle, housing a pair of ESA's Cluster spacecraft, on the launch pad at Baikonur in Kazakhstan, 12 July 2000.
Cluster is a collection of four spacecraft currently flying in formation around Earth. They relay information about how the solar wind affects our planet in three dimensions. The solar wind is the stream of subatomic particles given out by the Sun which can damage communications satellites and electrical systems on Earth.
The four Cluster spacecraft have spent several years passing in and out of our planet's magnetic field. Their mission is to complete the most-detailed investigation ever made into the ways in which the Sun and Earth interact.
The first pair of Cluster satellites lifted off on 16 July 2000, the second pair one month later. The mission is set to run operationally until December 2005.
