What are T-rays?

T-rays stand for terahertz radiation. It is used to scan airline passengers for explosives and illegal drugs. The rays are particularly effective, as they can see through clothing, paper, leather, plastic, wood, and ceramics. They don’t penetrate as well as x-rays, but they also don’t damage living tissue. They can read spectroscopic signatures, detecting the difference between, say, hair gel and an explosive.