A C5 Supergalaxy, one of the world’s largest planes, loading the AMS-02 experiment at Geneva Airport. Image courtesy CERN Bulletin

New life was breathed into the International Space Station (ISS) this year after NASA announced it will extend the ISS from 2015 to at least 2020.

The new deadline extends opportunities for science experimentation in the largest space research laboratory ever constructed. One of these experiments is the Alpha Magnetic Spectrometer (AMS-02), a detector that may help scientists understand why our universe exists and why there is more matter than anti-matter.

Most space-grade electronics are about ten years old, so the AMS-02 represents the newest and most advanced physics experiment in outer space to date. Currently, it is being tested and due to launch in February 2011. AMS-02 was shipped via Geneva airport to NASA this August in one of the largest planes in the world, a US Air Force C5 Super Galaxy.

Once aboard the ISS, AMS-02 will measure electrically charged particles partly left over from the big bang and partially synthesized in stars during nuclear fusion. These include electrons, positrons, atomic-nuclei, and perhaps the anti-nuclei that permeate our universe.

The AMS team is headed up by Nobel Prize-winning physicist Samuel Ting, who discovered the ‘charm’ quark in 1974. Quarks are elementary particles, with no known substructure, that are fundamental constituents of all visible matter. Thus, their project played a pivotal role in establishing the periodic system of quarks that science studies today.

AMS-02’s computing requirements are dwarfed by those of the LHC; however, the AMS team still expects to receive 15 terabytes (TB) of raw data per year from their detector — equal to 3,750 DVDs.

Two for one

There will be two computer control centers that will manage AMS-02 and its transmitted data. POCC (Payload Operations and Control Center) will operate the AMS detector from the ground while its brother, SOC (Science Operations Center), will process and store the conveyed data.

In essence, POCC will act as the brain and keep scientists in the loop while also monitoring real time video displays of AMS-02 in space. It will consist of 12 to 16 consoles, two data servers and an array of hard drive disks of up to 100 TB.

Initially, SOC will consist of a gateway computer, six servers and six production nodes, all containing Intel Xeon processors. Production nodes can be thought of as a uniform unit of linked computers. It will also be capable of holding up to 200 TB of data per year.

Physicists and system managers will operate the equipment and work in tandem — like both computer centers — to manage the hardware and software elements of the mission.

Technical diagram of AMS-02 detector. (Click to enlarge.) Image courtesy AMS-02

Cutting through the static

Once operational, AMS-02 will get an undisturbed view of cosmic particles in space and record the fluxes or changes of all particles that constitute cosmic rays to get a better idea of their composition, direction and energies. There may even be new particles yet to be discovered.

Understanding the cosmic rays that surround Earth is valuable because it helps the search for enigmatic dark matter that makes up just over 20% of matter in our universe. (Normal matter only consists of about 4%; the rest is dark energy, scientists think.)

Also, a more comprehensive understanding of these particles will improve designs of radiation shielding for prolonged space travel as NASA plans to send human astronauts to Mars.

Martin Pohl, an AMS-02 scientist from the University of Geneva states that our understanding of cosmic radiation has not moved much since cosmic rays were first discovered over a century ago. “This is intolerable for physicists since much of the known energy in the universe resides in cosmic rays," he said.

This project is equivalent to the Hubble Space Telescope, but for charged particles. “Cosmic radiation is part of our environment. It probably influences everything, from human genes to climate change!” said Martin.

—Adrian Giordani, iSGTW