Double Star

Double Star orbit

The European Space Agency (ESA (link opens in a new window)) and the Chinese National Space Administration (link opens in a new window) launched the two Double Star Programme (link opens in a new window) (DSP) satellites six months apart in December 2003 (TC-1) and July 2004 (TC-2) from launch sites in China.

The purpose of the DSP mission is to extend our knowledge of the magnetosphere using the two Tan Ce (Chinese for explorer) satellites. TC-1 was launched from the Xi Chang spaceport into an equatorial orbit and TC-2 was launched from the Tai Yuan spaceport into a polar orbit, with both satellites flying in highly elliptical orbits so that they sample many key regions of the magnetosphere. Each satellite has eight instruments on board sampling the plasma environment around the Earth. They will study magnetic reconnection, locate and understand the trigger mechanism for magnetic storms, and study the physical processes such as particle acceleration, diffusion, injection and upflowing ions in magnetic storms. Five of the instruments are common to both satellites, with eight of the instruments built in Europe and eight in China. Most of the European instruments have a heritage from ESA's Cluster mission and DSP coordinates its activities with Cluster. The nominal end of mission for Double Star was initially July 2005, but the mission was extended until the end of 2009.

Instruments on Double Star
(* Instrument originated in China)

Double Star

• FGM (link opens in a new window): Fluxgate Magnetometer (TC-1 and TC-2), located on a 3.5 metre boom measures the magnetic fields along the orbit.
  
  
• NUADU: Neutral Atom Imager (TC-2) monitors energetic neutral atoms in the magnetosphere particularly imaging the Earth's ring current.
  
  
• HIA (link opens in a new window): Hot Ion Analyser (TC-1) analyses the distribution functions of ions in the nearby (magnetosphere) space plasma and in the solar wind.
  
  
• PEACE (link opens in a new window): Plasma Electron and Current Experiment (TC-1 and TC-2) studies electrons in the space plasma.
  
  
• ASPOC (link opens in a new window) : Active Spacecraft Potential Control (TC-1) prevents a build-up of positive electrical charge on the satellite, using the measurements from PEACE.
  
  
• STAFF (link opens in a new window) / DWP (link opens in a new window): Spatio-Temporal Analysis of Field Fluctuations/Digital Wave Processor (TC-1) at the end of a 3.5 metre boom, studies waves (rapid variations in the magnetic fields) particularly in regions where the charged particles of the solar wind interact with the magnetosphere.
  
  
• LFEW *: Low Frequency Electromagnetic Wave Detector (TC-2)
• LEID *: Low Energy Ion Detector(TC-2)
• HID *: Heavy Ion Detector (TC-1 and TC-2)
• HEPD *: High Energy Proton Detector (TC-1 and TC-2)
• HEED *: High Energy Electron Detector (TC-1 and TC-2)

Links to other sites

ESA Double Star Project overview (link opens in a new window).