Some 70 representatives of the international Cluster scientific community came together last week for the 35th Cluster Science Working Team at the European Space Operations Centre (ESOC) in Darmstadt, Germany.
 
One of the highlights of the meeting was the first glimpse of the preliminary scientific data that has been returned from the four spacecraft during their commissioning campaign.
 
In some cases, the Principal Scientific Investigators (PIs) were able to present snapshots of data from a particular instrument on a single spacecraft, while others presented limited sets of data from all four spacecraft for the first time.
 
Although it was too early to carry out a detailed analysis of the new results, the scientists were very excited by the high quality of the data. It was immediately obvious that the instruments were revealing significant differences in the particle populations, electromagnetic fields and waves detected by each of the four satellites.
 
During an update on the status of the Cluster quartet, Deputy Project Scientist Michael Fehringer explained that commissioning of 30 instruments has already been completed, while checks on the remainder were well under way.
 
Everyone at the meeting praised the dedication and hard work of the engineers and mission operations team at ESOC during this exhausting three month period of commissioning.
 
The final pre-operational phase, starting on 7 December, will be the Cluster Interference Campaign. Over a period of two weeks, the science teams will work with their colleagues at ESOC and the Joint Science Operations Centre (JSOC) in the UK to determine how much (if at all) the 11 instruments on each spacecraft affect each other when they are simultaneously operational. This intensive check-out programme is scheduled to be completed shortly before the Christmas break.
 
Meanwhile, a minor alteration in the quartet’s spin plane was completed on 28 November, in order to ensure that their solar arrays capture as much sunlight as possible in the coming weeks. Additional constellation manoeuvres are planned for 2 – 21 December, when the spacecraft’s separations and orientations will be modified. The foursome will then be arranged in the perfect 600 km tetrahedral formation that will be required for Cluster’s investigations of the cusp regions over the Earth’s magnetic poles in late February 2001.
 
USEFUL LINKS FOR THIS STORY
 
* Cluster homepage
  http://sci.esa.int/cluster
* The instruments onboard Cluster
  http://sci.esa.int/content/doc/c6/1990_.htm
* Biographies Cluster II Team
  http://sci.esa.int/content/doc/ba/13498_.htm
 
IMAGE CAPTIONS:
 
[Image 1:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=8&cid=12&ooid=25378] The Science Working Team members came to ESOC for a two days meeting to discuss the status of the commissioning of the instruments and the first data acquired.
 
[Image 2:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=8&cid=12&ooid=25362] Cluster Principal Investigators. From left to right, B. Wilken (RAPID, D), A. Balogh (FGM, UK), D. Gurnett (WBD, USA), K. Torkar (ASPOC, A), P. Daly (RAPID, D), G. Gustafsson (EFW, S), P. Decreau (WHISPER, F), G. Paschmann (EDI, D), N. Cornilleau (STAFF, F), A. Fazakerley (PEACE, UK), M. Andre (EFW, S), H. Alleyne (DWP, UK), J.-M. Bosqued (CIS, F), P.-A. Lindqvist (WEC), C. P. Escoubet (PS, NL).
 
[Image 3:
http://sci.esa.int/content/searchimage/searchresult.cfm?aid=8&cid=12&ooid=25363] The Science Working Team during the Science session.