Big, beautiful photos of insane physics experiments chasing the 'ghost particle' around the world

Scientists call it the "ghost particle."

It has almost no mass, travels at essentially the speed of light, and evaded scientific confirmation for three decades.

Meet the neutrino, which scientists hope will help them answer dozens of critical questions about the universe, including why it's full of matter.

Neutrinos are produced when radioactive elements decay. They gush out of the sun, other stars, and even our own bodies. They also travel through huge amounts of matter without even flinching.

So how do you study a particle that can pass through a light-year of lead without being stopped? With some really big experiments. Take a look: