|a picture paints a thousand photons of human-emitted light|
that's what researchers from Kyoto University's Tohoku Institute of Technology found.
To learn more about this faint visible light, scientists in Japan employed extraordinarily sensitive cameras capable of detecting single photons. Five healthy male volunteers in their 20s were placed bare-chested in front of the cameras in complete darkness in light-tight rooms for 20 minutes every three hours from 10 a.m. to 10 p.m. for three days.
The researchers found the body glow rose and fell over the day, with its lowest point at 10 a.m. and its peak at 4 p.m., dropping gradually after that. These findings suggest there is light emission linked to our body clocks, most likely due to how our metabolic rhythms fluctuate over the course of the day. [source LIVESCIENCE]
NB: this is not the heat-vision that night-vision goggles pick up. This is light emitted from the body's processes. The 'angle' of this story is that, "If we can see the light emitted from our internal processes," we have at our fingertips an almost-instantaneous analytical tool for Human Health.