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The discovery of the ultraviolet radiation with wavelengths below 200 nm, ... Humans need some UV radiation to maintain adequate vitamin D levels.
Ultraviolet astronomy is the observation of electromagnetic radiation at ultraviolet wavelengths between approximately 10 and 320 nanometres; shorter wavelengths—higher energy photons—are studied by X-ray astronomy and gamma-ray astronomy. [1] Ultraviolet light is not visible to the human eye. [2]
Electromagnetic radiation with a wavelength between 380 nm and 760 nm (400–790 terahertz) is detected by the human eye and perceived as visible light. Other wavelengths, especially near infrared (longer than 760 nm) and ultraviolet (shorter than 380 nm) are also sometimes referred to as light, especially when the visibility to humans is not ...
The terms chemical and heat rays were eventually dropped in favor of ultraviolet and infrared radiation, respectively. [1] 1895 Discovery of the ultraviolet radiation below 200 nm, named vacuum ultraviolet (later identified as photons) because it is strongly absorbed by air, by the German physicist Victor Schumann [2] 1895
However, UV sensitivity has been reported in most insect species. [40] Bees and many other insects can detect ultraviolet light, which helps them find nectar in flowers. Plant species that depend on insect pollination may owe reproductive success to their appearance in ultraviolet light rather than how colorful they appear to humans.
The human eye can perceive light with wavelengths between roughly 350 (violet) and 700 (red) nanometres. Ultraviolet light has wavelengths between roughly 10 nm and 350 nm. UV light can be harmful to human beings and is strongly absorbed by the ozone layer. This makes it impossible to observe UV emission from astronomical objects from the
[clarification needed] The international symbol for types and levels of ionizing radiation (radioactivity) that are unsafe for unshielded humans. Radiation, in general, exists throughout nature, such as in light and sound. In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a ...
In the 19th century new developments such as the discovery of photography, Rowland's [40] invention of the concave diffraction grating, and Schumann's [41] works on discovery of vacuum ultraviolet (fluorite for prisms and lenses, low-gelatin photographic plates and absorption of UV in air below 185 nm) made advance to shorter wavelengths very fast.