New results from the particle detector attached outside the International Space Station show something else beside ordinary matter is generating cosmic rays, the lead researcher said Tuesday.
More cosmic ray detections are needed before scientists will know for sure if they're seeing telltale fingerprints of dark matter colliding or if they've found particles generated by highly magnetized, rotating neutron stars known as pulsars.
"We know something new has happened, but we still do not know the origin," Massachusetts Institute of Technology physicist Sam Ting, lead researcher of the 600-member Alpha Magnetic Spectrometer science team, said at a space station research conference in Chicago.
"In a short time, we'll really be able to resolve the mystery," he said.
Unlike visible or ordinary matter, dark matter cannot be directly detected by electromagnetic radiation. Yet scientists believe its gravity is responsible for keeping the galaxy -- and the universe for that matter -- together.
Dark matter and its even stranger, anti-gravity cousin, dark energy, which is credited with speeding up the universe's expansion, comprise about 95 percent of the known universe.