The Alpha Magnetic Spectrometer (AMS) is a particle physics experiment that was originally intended to be installed onto the International Space Station. Its purpose was to search the universe for unusual matter, such as dark matter and antimatter, by measuring cosmic rays.

However, only a prototype AMS (the Alpha Magnetic Spectrometer Investigation) was able to get into space when it went onboard space shuttle Discovery and the STS-91 mission in 1998, the final space shuttle mission to the Russian Mir space station. After the space shuttle Columbia was destroyed in 2003, the AMS mission was cancelled.

It is noted, that like the Hubble servicing mission, which was approved, rejected, and eventually approved, AMS has the possibility of being reinstated into a mission sometime in the next few years. It is, however, not officially scheduled on any shuttle mission in the future.

Within the Washington Post article, U.S. physicist Samuel C.C. Ting (from Massachusetts Institute of Technology), who first conceived of the AMS project and received the Nobel Prize in 1976, stated, “The credibility of the United States is at stake here, because NASA made a commitment to bring Columbus and AMS to the space station. After all this work, it would be a terrible blow if the instrument cannot be used."

On the other hand, Giovanni Bignami, president of the Italian Space Agency, stated in the same article, “Given all that has happened with the shuttle program, there is no reason to throw harsh words at NASA about this.”

However, like Ting, Bignami also stated, “… it would be a true international disgrace if this instrument ends up as a museum piece that never is used."