Neutrino detector to spot mysterious ghost particles around us

The $300-million detector in China took 9 years to build. Its location 2,297 feet underground protects it from pesky cosmic rays, radiation

Underneath a granite hill in southern China, a massive detector is nearly complete that will sniff out the mysterious ghost particles lurking around us.

The Jiangmen Underground Neutrino Observatory will soon begin the difficult task of spotting neutrinos: tiny cosmic particles with a mind-bogglingly small mass.

The detector is one of three being built across the globe to study these elusive ghost particles in the finest detail yet. The other two, based in the United States and Japan, are still under construction.

Spying neutrinos is no small feat in the quest to understand how the universe came to be. The Chinese effort, set to go online next year, will push the technology to new limits, said Andre de Gouvea, a theoretical physicist at Northwestern University who is not involved with the project. "If they can pull that off," he said, "it would be amazing."

What are neutrinos?

Neutrinos date back to the Big Bang, and trillions zoom through our bodies every second. They spew from stars like the sun and stream out when atomic bits collide in a particle accelerator.

Scientists have known about the existence of neutrinos for almost a century, but they're still in the early stages of figuring out what the particles really are.