^HUMANS GLOW IN THE DARK^

For better understanding :-

1. Human body actually emits visible light. The amount of light emitted is extremely small in quantity.

2. The levels of the light emitted by a human body fluctuates throughout the day.

3. The light emitted by human body has very low intensity. It has 1000 times less intensity compared to the light that is visible to naked eyes. This is reason why, the light emitted by a human body is not visible.

4. It is not that humans emit light. Scientists say that light is emitted by every living creature in this world and that the light emitted by majority of them is so weak that it is not visible to human eyes.

5. Human body emits light because of the chemical reactions that take place inside the body and involve free radicals.

6. Since the light emitted by human body is not visible, some may actually confuse it with infrared light. This is not true. Infrared radiation is actually an invisible form of light while the light emitted by human body is visible. It is just that the intensity is extremely low to be visible to eyes.

7. Human bioluminescence was confirmed by a group of Japanese scientists. They used cameras which were extraordinarily sensitive and were capable of detecting photons.

1. In the experiments conducted by the scientists, it was found that human bioluminescence is lowest at 10 AM and highest at 4 PM.

2. Based on the results of the experiments, the scientists concluded that bioluminescence in humans is directly connected to body clock and fluctuations in metabolic rhythms resulted in the fluctuations of bioluminescence.

3. The experiments revealed an interesting fact. It was found that faces showed more bioluminescence compared to the rest of the body.

4. The scientists concluded that body is less exposed to sunlight compared to face and the pigment (melanin) produced underneath the skin is stimulated by sunlight. This melanin contains fluorescent components. Thus more melanin in face means more bioluminescence.

5. Scientists say that since human bioluminescence is directly connected to metabolism, the faint light emitted by human body can actually be used for spotting medical conditions.

6. One may argue that what is considered to be bioluminescence is actually thermal signature of the body. This however is ruled out by the scientists. They found that areas of the body with brightest thermal image did not produce brightest light.

7. Human bioluminescence has no evolutionary role to play unlike in case of deep sea fish, glow worms, ostracods, fireflies etc.