Humans do not naturally emit visible light. While it is true that humans emit various forms of radiation, such as heat and electromagnetic radiation, this radiation is not typically in the visible spectrum.
All objects with a temperature above absolute zero emit thermal radiation, including humans. This thermal radiation, also known as blackbody radiation, is in the form of infrared radiation. Infrared radiation is not visible to the human eye but can be detected and measured using specialized instruments, such as infrared cameras or sensors.
The amount and characteristics of the radiation emitted by a human depend on factors such as body temperature, metabolic rate, and the surrounding environment. However, the wavelengths of the emitted infrared radiation generally fall within the infrared spectrum.
It's worth noting that humans also reflect and scatter the visible light that falls on them. This is why we can see each other and the objects around us. However, this is different from actively emitting light ourselves.
In summary, while humans do emit radiation, it is primarily in the form of non-visible infrared radiation due to body heat, rather than visible light.