The first joint Sino-European mission

• Two satellites launched on 29 December 2003 and 25 July 2004
• Mission partly ended 30 September 2007

Double Star is a joint project between China, which built both satellites, and Europe. Seven of the 16 instruments on the satellites are copies of instruments on Cluster. UK science teams are leading several of the scientific investigations.

The four Cluster and two Double Star satellites have been working together to explore the Sun's effect on our environment. Combining the results from the two missions improves the scientific findings from both.

With its mission now at an end, the first Double Star satellite was decommissioned in October 2007 - turning to dust as it re-entered Earth’s atmosphere. Double Star 2 remains operational.

For more information, visit ESA's Double Star homepage.

Mission facts

• Double Star involved two satellites - each designed, developed, launched, and operated by the China National Space Administration (CNSA).
  
  
• The two spacecraft were called TC-1 and TC-2, TC stands for 'Tan Ce' which is Chinese for 'Explorer'.
  
  
• The mission was the first pure science mission conducted by China and the first international science partnership in space involving China.
  
  
• Many of the scientists who developed the instruments for Cluster contributed replicas or spares to the Double Star project. This helped to reduce costs and speeded up the development process.
  
  
• Double Star's joint mission with Cluster was originally due to finish at the end of July 2005 but it was so successful it was extended until September 2007.

Technology

Each spacecraft consists of a cylinder 1.4 m in height with two long (2.5 m) booms sticking out from the sides.

The technology on Double Star is almost identical to that used on Cluster with one new instrument being designed by Europe specifically for the mission.

UK involvement

Three of the principal investigators from Double Star are from the UK - from the Mullard Space Science Laboratory, Imperial College and the University of Sheffield.

The STFC Rutherford Appleton Laboratory provided the European Payload Operations Centre which operated the seven European instruments used on board the two craft.