A report on Light, Sun and Radiation

A triangular prism dispersing a beam of white light. The longer wavelengths (red) and the shorter wavelengths (blue) are separated.
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Illustration of the relative abilities of three different types of ionizing radiation to penetrate solid matter. Typical alpha particles (α) are stopped by a sheet of paper, while beta particles (β) are stopped by an aluminum plate. Gamma radiation (γ) is dampened when it penetrates lead. Note caveats in the text about this simplified diagram.
The electromagnetic spectrum, with the visible portion highlighted
Illustration of the Sun's structure, in false color for contrast
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.
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Illustration of a proton-proton reaction chain, from hydrogen forming deuterium, helium-3, and regular helium-4.
Some kinds of ionizing radiation can be detected in a cloud chamber.
Beam of sun light inside the cavity of Rocca ill'Abissu at Fondachelli-Fantina, Sicily
Illustration of different stars's internal structure, the Sun in the middle has an inner radiating zone and an outer convective zone.
Graphic showing relationships between radioactivity and detected ionizing radiation
Due to refraction, the straw dipped in water appears bent and the ruler scale compressed when viewed from a shallow angle.
High-resolution image of the Sun's surface taken by the Daniel K. Inouye Solar Telescope (DKIST)
Gamma radiation detected in an isopropanol cloud chamber.
Hong Kong illuminated by colourful artificial lighting.
During a total solar eclipse, the solar corona can be seen with the naked eye, during the brief period of totality.
Alpha particle detected in an isopropanol cloud chamber
Pierre Gassendi.
The Sun's transition region taken by Hinode's Solar Optical Telescope
Electrons (beta radiation) detected in an isopropanol cloud chamber
Christiaan Huygens.
Sunlight and glare seen overlooking from the International Space Station
The electromagnetic spectrum
Thomas Young's sketch of a double-slit experiment showing diffraction. Young's experiments supported the theory that light consists of waves.
Once outside the Sun's surface, neutrinos and photons travel at the speed of light
In electromagnetic radiation (such as microwaves from an antenna, shown here) the term "radiation" applies only to the parts of the electromagnetic field that radiate into infinite space and decrease in intensity by an inverse-square law of power so that the total radiation energy that crosses through an imaginary spherical surface is the same, no matter how far away from the antenna the spherical surface is drawn. Electromagnetic radiation includes the far field part of the electromagnetic field around a transmitter. A part of the "near-field" close to the transmitter, is part of the changing electromagnetic field, but does not count as electromagnetic radiation.
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Visible light photograph of sunspot
Measurements from 2005 of solar cycle variation during the previous 30 years
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The size of the current Sun (now in the main sequence) compared to its estimated size during its red-giant phase in the future
The Solar System, with sizes of the Sun and planets to scale. The terrestrial planets are on the right, the gas and ice giants are on the left.
The Trundholm sun chariot pulled by a horse is a sculpture believed to be illustrating an important part of Nordic Bronze Age mythology.
Sol, the Sun, from a 1550 edition of Guido Bonatti's Liber astronomiae.
False-color image taken in 2010 as seen in 30.4-nanometer ultraviolet light wavelength
A false-color of a coronal hole on the Sun forming a question mark (22 December 2017)
A false-color solar prominence erupts in August 2012, as captured by the Solar Dynamics Observatory
The Sun seen from Earth, with glare from the lenses. The eye also see glare when looked towards the Sun directly.
Sun and Immortal Birds Gold Ornament by ancient Shu people. The center is a sun pattern with twelve points around which four birds fly in the same counterclockwise direction, Shang dynasty

It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light, ultraviolet, and infrared radiation.

- Sun

The main source of natural light on Earth is the Sun.

- Light

The designation "radiation" excludes static electric, magnetic and near fields.

- Light

electromagnetic radiation, such as radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma radiation (γ)

- Radiation

This temperature gradient is less than the value of the adiabatic lapse rate and hence cannot drive convection, which explains why the transfer of energy through this zone is by radiation instead of thermal convection.

- Sun

Herschel, like Ritter, used a prism to refract light from the Sun and detected the infrared (beyond the red part of the spectrum), through an increase in the temperature recorded by a thermometer.

- Radiation
A triangular prism dispersing a beam of white light. The longer wavelengths (red) and the shorter wavelengths (blue) are separated.

1 related topic with Alpha

Overall
Levels of ozone at various altitudes (DU/km) and blocking of different bands of ultraviolet radiation: In essence, all UVC is blocked by diatomic oxygen (100–200 nm) or by ozone (triatomic oxygen) (200–280 nm) in the atmosphere. The ozone layer then blocks most UVB. Meanwhile, UVA is hardly affected by ozone, and most of it reaches the ground. UVA makes up almost all UV light that penetrates the Earth's atmosphere.

Ultraviolet

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Levels of ozone at various altitudes (DU/km) and blocking of different bands of ultraviolet radiation: In essence, all UVC is blocked by diatomic oxygen (100–200 nm) or by ozone (triatomic oxygen) (200–280 nm) in the atmosphere. The ozone layer then blocks most UVB. Meanwhile, UVA is hardly affected by ozone, and most of it reaches the ground. UVA makes up almost all UV light that penetrates the Earth's atmosphere.
A 380 nanometer UV LED makes some common household items fluoresce.
Ultraviolet photons harm the DNA molecules of living organisms in different ways. In one common damage event, adjacent thymine bases bond with each other, instead of across the "ladder". This "thymine dimer" makes a bulge, and the distorted DNA molecule does not function properly.
Sunburn effect (as measured by the UV index) is the product of the sunlight spectrum (radiation intensity) and the erythemal action spectrum (skin sensitivity) across the range of UV wavelengths. Sunburn production per milliwatt of radiation intensity is increased by nearly a factor of 100 between the near UV‑B wavelengths of 315–295 nm
Demonstration of the effect of sunscreen. The man's face has sunscreen on his right side only. The left image is a regular photograph of his face; the right image is of reflected UV light. The side of the face with sunscreen is darker because the sunscreen absorbs the UV light.
Signs are often used to warn of the hazard of strong UV sources.
UV damaged polypropylene rope (left) and new rope (right)
IR spectrum showing carbonyl absorption due to UV degradation of polyethylene
A portrait taken using only UV light between the wavelengths of 335 and 365 nanometers.
Aurora at Jupiter's north pole as seen in ultraviolet light by the Hubble Space Telescope.
A bird appears on many Visa credit cards when they are held under a UV light source
After a training exercise involving fake body fluids, a healthcare worker's personal protective equipment is checked with ultraviolet light to find invisible drops of fluids. These fluids could contain deadly viruses or other contamination.
A collection of mineral samples brilliantly fluorescing at various wavelengths as seen while being irradiated by UV light.
Effects of UV on finished surfaces in 0, 20 and 43 hours.
A low-pressure mercury vapor discharge tube floods the inside of a hood with shortwave UV light when not in use, sterilizing microbiological contaminants from irradiated surfaces.
Entomologist using a UV light for collecting beetles in Chaco, Paraguay.

Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays.

The terms "chemical rays" and "heat rays" were eventually dropped in favor of ultraviolet and infrared radiation, respectively.

The Sun emits ultraviolet radiation at all wavelengths, including the extreme ultraviolet where it crosses into X-rays at 10 nm.