UPDATE for 11 a.m. ET:The first official announcements for today's news have been released. See the latest story here:Dark Matter Possibly Found by $2 Billion Space Station Experiment.

NASA will unveil the first discoveries from a powerful $2 billion particle physics experiment on the International Space Station in what could be a major vindication for the science tool, which almost never made it into space.

The space agency will hold a press conference at 1:30 p.m. EDT (1830 GMT) today, April 3, to reveal the first science results from the experiment, called the Alpha Magnetic Spectrometer. You can watch the AMS science results live on SPACE.com, via NASA TV.

The Alpha Magnetic Spectrometer is an advanced cosmic-ray detector designed to seek out signs of antimatter and elusive dark matter from its perch on the backbone-like main truss of the International Space Station. More than 200 scientists representing 16 countries and 56 institutions are part of the science team, which is led by Nobel laureate Samuel Ting, a physicist at MIT.

"AMS is a state-of-the-art cosmic ray particle physics detector located on the exterior of the International Space Station," NASA officials said in an announcement Tuesday (April 2). [See photos of the Alpha Magnetic Spectrometer in space]

NASA and the AMS team have not revealed exactly what the first science results from AMS will be, but Ting has assured that it will be a significant announcement.

"It will not be a minor paper," Ting said on Feb. 17 during the annual meeting of the American Association for the Advancement of Science in Boston, adding that it would represent a "small step" toward understanding the true nature of dark matter, even if it is not the final answer.

The spectrometer consists of a huge, 3-foot wide magnet that bends the paths of cosmic particles and steers them into special detectors designed to measure particles' charge, energy and other properties. The complicated space experiment was 16 years in the making, but despite its lofty mission, the 7-ton AMS almost never flew.

In fact, NASA canceled the space shuttle mission originally slated to launch AMS to the space station in 2005. At the time, the space agency cited safety concerns following the 2003 space shuttle Columbia accident an event that led directly to the space shuttle fleet's retirement in 2011.

But NASA's decision to cancel the AMS mission did not sit well with the science community. Scientists launched a persistent campaign to resurrect the AMS launch, including an intense lobbying effort to sway lawmakers in Congress to their side.

See more here:

NASA to Announce Major Astrophysics Discovery Today