Cluster Status Report - November 2007
08 November 2007 16:27Mission Status
Constellation manoeuvres were finished on 4 July. C3 and C4 were put at 17 km from each other, their closest separation distance in the Cluster lifetime. This constellation will allow investigating very small plasma structures in the tail of the magnetosphere.
On 25 July attitude manoeuvres were performed to keep the spacecraft spin plane close to the ecliptic. Cluster had again entered an eclipse season, which lasted until 28 September. The operations strategy had been changed slightly after the battery conditioning as it was found that the battery capacity on C3 was lower than expected. The decision was taken to run also this spacecraft in decoder only mode. C4 had also less capacity than expected and the FGM (magnetometer) and the SSR (data recorder) had to be switched off during two eclipses. These two eclipses, on 21 and 24 September, turned out to be a heavy load for the ESOC operations team since two spacecraft had to be operated in decoder-only mode at the same time. To support these operations a special automatic procedure to recover the spacecraft was successfully tested.
Operations and Archiving
JSOC and ESOC have operated the spacecraft and instruments as planned in the Master Science Plan. The average science data return of all spacecraft from 7 July 2007 until end of August was 98.7%. JSOC is looking at the conjunctions between Cluster the NASA Themis mission to maximize the data acquisition (burst mode) during the best conjunctions. The Cluster Active Archive (CAA) development continues steadily.
The CAA has 481 registered users as of end August 2007. The downloading rate was 21 Gbytes in August with a large portion of FGM (magnetometer), EFW (electric field) and CIS (Ion) data. The 15th Cluster workshop in March 2008, to be held in Tenerife, will include special sessions on the CAA products and tools and a hands-on workshop at the end.