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By some estimates, trillions of neutrinos pass through every square meter of the Earth's surface every second. They leave no trace, but occasionally their presence can be detected.

On rare occasions, a neutrino will smash directly into a proton or neutron. From the crash, a new particle known as a muon will be created. Unlike neutrinos, muons are detectable. The faint blue light given off by muons can be picked up by the photomultipliers.

Much like a billiard ball hit straight on, the muon travels in the same path as the neutrino, which allows scientists to determine where in the universe the neutrino came from. Thus, a downward-looking telescope can explore the far reaches of space.

Sources of the neutrinos are many, including supernovas, quasars and neutron stars in our own galaxy and elsewhere, and massive black holes throughout the universe.

In essence, neutrino telescopes open a new window to the universe not available from conventional astronomy, said Bob Morse, a UW professor of physics who helped oversee construction of AMANDA and is working for funding of the bigger project.

And that window could become a veritable panorama in the near future.

Dubbed Ice Cube, the new project will include 5,000 photomultiplier modules buried throughout a cubic kilometer of ice. It will be able to detect more faint and distant objects.

Like the optical telescope and more advanced astronomy equipment that followed, the ice-bound neutrino telescope will advance our knowledge of space and how the universe was formed, Morse said.

But its biggest dividend likely will be the unexpected breakthroughs it brings, he said.

"It's like when the world was uncharted," he said. "Every time someone opened up a new window to the universe, new phenomena were discovered."