NASA says it's giving $4.4 million to five U.S. universities to help the agency build a telescope for deployment on the International Space Station in 2017.

University scientists along with researchers at NASA's Marshall Space Flight Center in Alabama will join an international project to build an 8-foot ultraviolet telescope, the Extreme Universe Space Observatory, to search for the mysterious source of the most energetic particles in the universe from the space station's Japanese Experiment Module.

The origin of these energetic particles, called ultra high-energy cosmic rays, has remained a mystery since they were discovered more than 50 years ago, researchers said.

"The science goal is to discover the sources of ultra high-energy cosmic rays by observing their traces in the atmosphere looking 248 miles from the ISS down to the surface," said astronomy and astrophysics Professor Angela Olinto of the University of Chicago, one of the participating institutions.

Olinto said the believes the Extreme Observatory could be the first step toward using the entire Earth atmosphere for studying subatomic particle interactions at energies far exceeding what the most powerful man-made particle accelerators on Earth can currently produce.

"In my opinion it's the way to the future," said Olinto, who leads the U.S. collaboration on the project.