An Alpha Magnetic Spectrometer (AMS) particle detector is due to launch onboard the space Shuttle Endeavour. The AMS will then be installed on the International Space Station from where it will explore the Universe for a period of over 10 years.

AMS is a particle detector that will track incoming charged particles such as protons, electrons and atomic nuclei that constantly bombard our planet. By studying the flux of these cosmic rays with very high precision, AMS will have the sensitivity to identify a single antinucleus among a billion other particles. This would signal the existence of large amounts of antimatter elsewhere in the Universe. If successful, this will shed light on why we live in a Universe made of matter, if matter and antimatter were created in equal amounts at the Big Bang.

AMS may also bring an important contribution to the search for the mysterious dark matter that would account for about 25 % of the total mass-energy balance of the Universe. If dark matter is composed of supersymmetric particles, AMS could detect it indirectly by recording an anomaly in the flux of cosmic rays.

• The launch of AMS can be followed live via webcast at: http://webcast.cern.ch (Friday 29 April 2011 from 20:30 to 21:30 (Europe/Zurich) at CERN)
  Questions can be asked during the webcast by sending them to @cern on twitter
• More information about AMS