A report on Light, Sun and Visible spectrum

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

White light is dispersed by a prism into the colors of the visible spectrum.

The electromagnetic spectrum, with the visible portion highlighted

Illustration of the Sun's structure, in false color for contrast

Illustration of a proton-proton reaction chain, from hydrogen forming deuterium, helium-3, and regular helium-4.

Newton's color circle, from Opticks of 1704, showing the colors he associated with musical notes. The spectral colors from red to violet are divided by the notes of the musical scale, starting at D. The circle completes a full octave, from D to D. Newton's circle places red, at one end of the spectrum, next to violet, at the other. This reflects the fact that non-spectral purple colors are observed when red and violet light are mixed.

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.

Newton's observation of prismatic colors (David Brewster 1855)

$Due to refraction, the straw dipped in water appears bent and the ruler scale compressed when viewed from a shallow angle.$

High-resolution image of the Sun's surface taken by the Daniel K. Inouye Solar Telescope (DKIST)

How visible light interacts with objects to make them colorful

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.

Approximation of spectral colors on a display results in somewhat distorted chromaticity

The Sun's transition region taken by Hinode's Solar Optical Telescope

Earth's atmosphere partially or totally blocks some wavelengths of electromagnetic radiation, but in visible light it is mostly transparent

Sunlight and glare seen overlooking from the International Space Station

$Thomas Young's sketch of a double-slit experiment showing diffraction. Young's experiments supported the theory that light consists of waves.$

Once outside the Sun's surface, neutrinos and photons travel at the speed of light

Measurements from 2005 of solar cycle variation during the previous 30 years

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

Electromagnetic radiation in this range of wavelengths is called visible light or simply light.

- Visible spectrum

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

- Light

Generally, electromagnetic radiation (EMR) is classified by wavelength into radio waves, microwaves, infrared, the visible spectrum that we perceive as light, ultraviolet, X-rays and gamma rays.

- Light

For example, Helium was first detected by analysis of the spectrum of the sun.

- Visible spectrum

During early studies of the optical spectrum of the photosphere, some absorption lines were found that did not correspond to any chemical elements then known on Earth.

- Sun

3 related topics with Alpha

Infrared

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This false-color infrared space telescope image has blue, green and red corresponding to 3.4, 4.6, and 12 μm wavelengths, respectively.

Plot of atmospheric transmittance in part of the infrared region

Materials with higher emissivity appear closer to their true temperature than materials that reflect more of their different-temperature surroundings. In this thermal image, the more reflective ceramic cylinder, reflecting the cooler surroundings, appears to be colder than its cubic container (made of more emissive silicon carbide), while in fact, they have the same temperature.

Active-infrared night vision: the camera illuminates the scene at infrared wavelengths invisible to the human eye. Despite a dark back-lit scene, active-infrared night vision delivers identifying details, as seen on the display monitor.

Hyperspectral thermal infrared emission measurement, an outdoor scan in winter conditions, ambient temperature −15 °C, image produced with a Specim LWIR hyperspectral imager. Relative radiance spectra from various targets in the image are shown with arrows. The infrared spectra of the different objects such as the watch clasp have clearly distinctive characteristics. The contrast level indicates the temperature of the object.

Infrared light from the LED of a remote control as recorded by a digital camera

Reflected light photograph in various infrared spectra to illustrate the appearance as the wavelength of light changes.

Infrared hair dryer for hair salons, c. 2010s

IR satellite picture of cumulonimbus clouds over the Great Plains of the United States.

The greenhouse effect with molecules of methane, water, and carbon dioxide re-radiating solar heat

Beta Pictoris with its planet Beta Pictoris b, the light-blue dot off-center, as seen in infrared. It combines two images, the inner disc is at 3.6 μm.

An infrared reflectogram of Mona Lisa by Leonardo da Vinci

Thermographic image of a snake eating a mouse

Infrared radiation was discovered in 1800 by William Herschel.

Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light.

IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz).

Slightly more than half of the energy from the Sun was eventually found, through Herschel's studies, to arrive on Earth in the form of infrared.

Sunlight

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Sunrise over the Gulf of Mexico and Florida. Taken on 20 October 1968 from Apollo 7.

Sunlight on Mars is dimmer than on Earth. This photo of a Martian sunset was imaged by Mars Pathfinder.

Solar irradiance spectrum at top of atmosphere, on a linear scale and plotted against wavenumber

Sunlight shining through clouds, giving rise to crepuscular rays

Spectrum of the visible wavelengths at approximately sea level; illumination by direct sunlight compared with direct sunlight scattered by cloud cover and with indirect sunlight by varying degrees of cloud cover. The yellow line shows the power spectrum of direct sunlight under optimal conditions. To aid comparison, the other illumination conditions are scaled by the factor shown in the key so they match at about 470 nm (blue light).

Sunlight penetrating through a forest canopy in Germany

Édouard Manet: Le déjeuner sur l'herbe (1862-63)

Téli verőfény ("Winter Sunshine") by László Mednyánszky, early 20th century

Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light.

When direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat.

Electromagnetic spectrum

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Range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies.

A diagram of the electromagnetic spectrum, showing various properties across the range of frequencies and wavelengths

Plot of Earth's atmospheric opacity to various wavelengths of electromagnetic radiation. This is the surface-to-space opacity, the atmosphere is transparent to longwave radio transmissions within the troposphere but opaque to space due to the ionosphere.

Plot of atmospheric opacity for terrestrial to terrestrial transmission showing the molecules responsible for some of the resonances

The amount of penetration of UV relative to altitude in Earth's ozone

This frequency range is divided into separate bands, and the electromagnetic waves within each frequency band are called by different names; beginning at the low frequency (long wavelength) end of the spectrum these are: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays at the high-frequency (short wavelength) end.

The Sun emits its peak power in the visible region, although integrating the entire emission power spectrum through all wavelengths shows that the Sun emits slightly more infrared than visible light.

The wavelength of UV rays is shorter than the violet end of the visible spectrum but longer than the X-ray.