Phobos-Grunt and Yinghuo-1 (DIM, YPP-i1, YPP-i2)

The Chinese satellite Yinghuo-1 was intended to fly to Mars together with the spacecraft Phobos-Grunt, which would land on the Martian moon Phobos. After the launch in 2011, the spacecraft went into Earth orbit, but the kick-off motor which would send it towards Mars failed to fire. The combined spacecraft eventually descended into the Earth’s atmosphere and burned up.

DIM. Photo: IRF

 IRF built and developed three ion mass spectrometers for the mission:

  • A Detector for Ions at Mars (DIM), located on the Phobos-Grunt spacecraft. The associated control computer was built at the Russian Space Institute, IKI.
  • Two ion mass spectrometers (YPP-i1 and YPP-i2) on the Yinghuo-1 satellite. Both belonged to the sensor pack Yinghuo Plasma Package, (YPP). The associated electron sensor was built at the Chinese National Space Center, NSSC.

The three ion mass spectrometers would have simultaneously studied the interaction between the solar wind (a flow of charged atoms from the sun) and the Mars atmosphere from different positions.

YPP-i1 and YPP-i2. Photo: IRF

More information:
Dr Martin Wieser, researcher and project manager, IRF,

Created by Annelie Klint Nilsson at

Last modified by Annelie Klint Nilsson at