Six months after the four Cluster spacecraft congregated in Earth orbit, scientists are beginning to gather the first scientific results from ESAís unique mission to explore the magnetosphere ñ the magnetic shield that surrounds our planet.

To mark the beginning of Clusterís operational phase, members of the media are invited to attend a special press event at ESA Headquarters on 16 February, starting at 10h30.

During the meeting, the ESA Director of Science Professor Roger-Maurice Bonnet and representatives of the Cluster project and the science teams will summarise Clusterís quest to investigate the Sun-Earth connection, describe the current status of this unique mission and present some of the exciting results that have already been obtained from the mini-flotilla.

Cluster Background

Launched in pairs last summer, the Cluster quartet – Salsa, Samba, Rumba and Tango – have recently completed a highly complex check-out which involved 105 separate spacecraft manoeuvres ñ an all-time record. After deployment of 16 45-metre wire booms and in-orbit testing of 44 scientific instruments (two more world records), the commissioning phase is now completed and scientists are beginning to see the fruits of their labour.

During the next two years, Cluster will join ESAís Solar and Heliospheric Observatory (SOHO) spacecraft in exploring the interaction between Earthís magnetic field and the electrically charged particles swept along in the solar wind.

This will be a particularly hectic and exciting period, since it coincides with the peak of the 11-year cycle of solar activity. At such times, explosive solar flares and coronal mass ejections buffet our planet, potentially causing widespread power cuts, disrupting radio and satellite communications and generating colourful auroral displays.

By flying in tetrahedral formation, the Cluster quartet will provide the most detailed information ever obtained about the physical processes that take place as swarms of energetic particles invade near-Earth space. For the first time, scientists will be able to study in three dimensions the rapidly unfolding events taking place between 19 000 and 119 000 kilometres above our heads.


For more information, please contact:

ESA ñ Communication Department

Media Relations Office

Tel: +33 (0)

Fax: +33 (0)

Alberto Gianolio, ESA Cluster Deputy Project Manager

Tel: +31 71 565 3394


Philippe Escoubet, ESA Cluster Project Scientist

Tel: +31 71 565 3454



Further information on Cluster and the ESA Science Programme can be found on the Worldwide Web at:



Programme of the event

(ESA/HQ – Paris – 16 February, 2001 – 10h30 CET)


10:30 IntroductionAlberto Gianolio, ESA – Cluster Deputy Project Manager


10:40 Science results

10:40 Dr. Philippe Escoubet, ESA – Cluster Project Scientist

10:50 Dr. Nicole Cornilleau-Wehrlin, CETP, France – Principal Investigator for the STAFF (*) Experiment

11:00 Professor Andre Balogh, Imperial College, London ñ Principal Investigator for the FGM (**) Experiment


11:10 ConclusionsProfessor Roger-Maurice Bonnet, ESA Director of Science


11:15 Question & Answer session


11:30 End of event

(*) STAFF: Spatio-Temporal Analysis of Field Fluctuations

(**) FGM: Fluxgate Magnetometer

Press Conference Cluster first results


16 February 2001 – 10h30

ESA, 8/10 rue Mario Nikis – 75015-Paris


First name : _________________________ Surname : _____________________

Media : __________________________________________________________

Address : ______________________________________________________




Tel: ___________________________ Fax : __________________________

Mobile : ________________________ e-mail : ________________________


( ) I will be attending the event

( ) I will not be attending