Cluster II meets the media during London workshop
24 September 1999On 22 September, members of the Cluster II team took time off from athree-dayworkshop at Imperial College, London, to meet the press. During thebriefing, whichwas jointly organised by ESA and the UKs Particle Physics and AstronomyResearchCouncil (PPARC), members of the media were given an overview of the uniquemission to map the Earths magnetosphere in three dimensions, and informedof theprojects current status.
The meeting was opened by Dr. Ian Corbett, Director of Science and Deputy Chief Executive of PPARC, who spoke of the project's high priority for UK and European space science.
"Here we see European collaboration at its very best - between countries, in ESA, between industries, and between scientists," he said.
Cluster II project manager John Ellwood then provided an historical perspective on the mission's remarkable recovery after the tragic loss of the first Cluster spacecraft.
"In only three years - half the time it took to build Cluster I - we will have succeeded in building four almost identical spacecraft," he said. "This could only have been achieved by the determination and dedication of scientists and engineers in many different countries."
Describing the current status of the programme, he explained that two of the four spacecraft (FM 6 and 7) have already completed their test schedule, while installation of the payload on a third satellite (FM 8) will be completed in the near future. Delivery of the remaining scientific instruments is scheduled for early October, when the scientific experiments will be integrated with the fourth and final spacecraft, FM 5.
ESA project scientist Dr. Philippe Escoubet went on to summarise the unique scientific contribution that Cluster II will make to our knowledge of near-Earth space. As the Sun approaches the peak in its 11-year cycle of activity, the Cluster spacecraft will provide the first three dimensional map of the magnetosphere. They will also detect small-scale variations in electrical and magnetic fields as the charged particles of the supersonic solar wind slam into our planet's magnetic shield.
London was a particularly suitable location to hold this event, since three of the scientific principal investigators on Cluster II are from the UK. One of these PIs, Professor Andre Balogh, began with a personal account of his feelings when the original Cluster mission was scattered over the swamps of French Guiana after the launch failure of the first Ariane 5 rocket.
However, the main thrust of his presentation was to emphasise the important contribution Cluster II will make to scientific knowledge and its relevance to a modern, high-tech society, which relies on satellites and the ionosphere for telecommunications, mobile phones and Earth observation.
The final presentation was given by Mike Rickett, Director of Science and Radar Observation at Matra Marconi Space (MMS), who was representing UK industry. MMS-UK has played a major role in the design and fabrication of each spacecraft's onboard rocket engine (the reaction control subsystem) and their attitude and control subsystem, as well as providing specialist support for the launch campaign in Russia.
Other contributors from UK industry include Dowty Aerospace, which has provided six titanium propellant tanks for each spacecraft; GEC Marconi which has built sensitive instruments to measure spacecraft stability; and ARC-UK which produces the propellants for the Cluster II main engines.
The press briefing was a fairly short diversion during a three-day scientific workshop devoted to multipoint / multiscale measurements of plasma (gas composed of charged particles such as electrons and protons).
Some 150 scientists from all over Europe, as well as the United States, China and Russia, came to London for the meeting. During the first session, they listened respectfully while Hugo Alleyne from the University of Sheffield paid tribute to Les Woolliscroft, formerly principal investigator on the DWP instrument, who died in 1996, several months before the original Cluster launch.
Over the next few days, the science team discussed in detail how to analyse data coming simultaneously from the four Cluster II spacecraft, and also how to co-ordinate the Cluster II mission with other space missions and ground-based observatories.
"The more information we can obtain, the better our understanding of what is taking place in space between 19 000 and 119 000 km above our heads," explained Philippe Escoubet.
"Measurements taken when the four Cluster II spacecraft are only a few hundred kilometres apart provide fundamental information on the small-scale physical processes taking place in different regions of the magnetosphere," he said.
"Measurements from many, widely spaced sites give us global information on Earth's magnetic field and its responses to changes in the solar wind. All of this data then helps us to build up models and compare them with what happens in the real world."