Bending a glow stick and shaking it marks the initial action. This breaks an inner barrier, mixing the contents within the plastic tube.
Right after, the glow stick shows no visible change. It stays a clear, flexible tube filled with motionless liquid, producing no light in any setting.
Seconds pass—often 10 to 30—while the stick remains outwardly the same. Whether examined closely or waved around, no glow appears, and it feels no different to the touch.
Then, the liquid inside begins to emit a visible glow. A steady light radiates from the tube, making the color within brightly observable even in dim conditions.
The interval between activation and glow reveals a period defined by latency, where the action precedes any sign of light by a distinct wait.