Did you know that you are a light source? Discovering surprising details about what it is to be human never gets old. That we give off light and that we change luminosity over the course of a day was verified in 2009:
Amazing pictures of “glittering” human bodies have been released by Japanese scientists who have captured the first ever images of human “bioluminescence”.
Although it has been known for many years that all living creatures produce a small amount of light as a result of chemical reactions within their cells, this is the first time light produced by humans has been captured on camera.
Writing in the online journal PLoS ONE, the researchers describe how they imaged volunteers’ upper bodies using ultra-sensitive cameras over a period of several days. Their results show that the amount of light emitted follows a 24-hour cycle, at its highest in late afternoon and lowest late at night, and that the brightest light is emitted from the cheeks, forehead and neck.
Strangely, the areas that produced the brightest light did not correspond with the brightest areas on thermal images of the volunteers’ bodies.
The human body literally glimmers. The intensity of the light emitted by the body is 1000 times lower than the sensitivity of our naked eyes. Ultraweak photon emission is known as the energy released as light through the changes in energy metabolism. We successfully imaged the diurnal change of this ultraweak photon emission with an improved highly sensitive imaging system using cryogenic charge-coupled device (CCD) camera. We found that the human body directly and rhythmically emits light. The diurnal changes in photon emission might be linked to changes in energy metabolism. …
Bioluminescence, which is weak but visible, is sometimes produced in living organisms, such as fireflies or jellyfish, as the result of specialized enzymatic reactions that require adenosine triphosphate. However, virtually all living organisms emit extremely weak light, spontaneously without external photoexci-tation. This biophoton emission is categorized in different phenomena of light emission from bioluminescence, and is believed to be a by-product of biochemical reactions in which excited molecules are produced from bioenergetic processes that involves active oxygen species. Human body is glimmeringwith light of intensity weaker than 1/1000 times the sensitivity of naked eyes. By using a sensitive charge-coupled-device (CCD) camera with the ability to detect light at the level of a single photon, we succeeded in imaging the spontaneous photon emission from human bodies.via Plos