A type of solar eclipse that occurs when the sun is at perihelion and the moon is at apogee. Because the apparent size of the moon is insufficient to cover the sun, the outer edge of the solar disc remains visible, creating a ringlike formation of...

Name originally given to the sun's infrared radiation by Sir William Herschel in his Philosophical Transactions of 1800.

The sunlight that extends to the earth after scattering from other solar bodies, mostly from meteorite dust of radii...

An instrument in which an image of the sun is scanned by the entrance slit of a monochromator, the exit slit simultaneously...

A feature in the chromosphere of the sun formed by a jet of gas that reaches from the chromosphere into the corona and has...

Solar regions characterized by low density and open magnetic fields where high-speed solar wind streams originate....

Phototherapy is a medical treatment that involves the use of light to treat various conditions, particularly those related...

A system of Japanese origin that utilizes Fresnel lenses and a fiber optic network to transmit sunlight to otherwise...

Optoelectronics is a branch of electronics that focuses on the study and application of devices and systems that use light...

A spectroradiometer is a device used to measure the intensity of light at different wavelengths across the electromagnetic...

Rayleigh scattering is a phenomenon that occurs when light waves interact with particles or molecules that are much smaller...

Controlled beam technology that introduces beams of sunlight through holes in a roof that are relayed throughout the...

Quantum efficiency (QE) is a measure of the effectiveness with which a device or system, typically in the context of...

The unit generally used to express distances within the solar system, and sometimes to measure interstellar distances....

A group of solar cells that are electrically contacted and physically arranged so that they may be oriented in the direction...

Polarization refers to the orientation of oscillations in a transverse wave, such as light waves, radio waves, or other...

Characterizes an Earth-orbiting satellite whose orbit plane is near polar and positioned at an altitude that allows it to...

A measure of the optical path length for light traveling from the sun or other celestial source through Earth's atmosphere...

Ultraviolet reflectance refers to the ability of a material or surface to reflect UV light. Ultraviolet light is...

A telescope in which a mask occults the solar disk, generating an artificial eclipse and allowing observation and recording...

The dark absorption lines observed in the spectrum of the photosphere of the sun. There are thousands of these lines, the...

A device for converting sunlight into electrical energy, consisting of a sandwich of P-type and N-type semiconducting...

A device used in solar systems to direct mirror-reflected sunlight to a heat absorber and heat-driven engine, which turns a...

A light source, such as the sun or an incandescent lamp, that freely penetrates ordinary glass bulbs and emits in the...

A layer between the corona and the photosphere of the sun; its emission is overwhelmed by light emitted by the underlying,...

1. That action occurring when light passes through an optical interface at other than normal incidence, i.e., refraction. 2....

Inertial fusion energy (IFE) refers to a proposed method of generating electricity by harnessing the energy released from...

An optical system that is designed to produce a high temperature in a specified area by the optical direction and...

The image of the sun produced by a spectroheliograph.

The graph of a curve describing the spectral irradiance of extraterrestrial sunlight.

Mie scattering, named after the German physicist Gustav Mie, refers to the scattering of electromagnetic radiation (such as...

One of two types of solar time - the other being apparent solar time - the mean solar time is the time measured by the...

A collector for photovoltaic power generation that consists of a thin plate that strongly absorbs sunlight striking its...

Uniform measure of time based on dynamics law and calculated according to planetary orbital paths; specifically, Earth's...

The angle subtended by the mean distance of the Earth from the sun at the distance of a given star from the sun.

Family of deterministic models of plant canopy reflectance that provides deterministic formulation for each necessary...

The constant outward flow of weakly magnetized plasma from the sun that is deflected by the magnetic field of the earth and,...

Plasma formed by heat radiation from the sun.

A Fresnel lens is a type of optical lens that consists of a series of concentric grooves or steps carved into a flat, thin...

A photovoltaic cell, commonly known as a solar cell, is a semiconductor device that directly converts light energy into...

The simulation of solar radiation in the infrared and ultraviolet spectrum for the analysis of extraterrestrial sunlight and...

Phototoxicity refers to the harmful effects caused by exposure to light, particularly intense or ultraviolet (UV) light, on...

The apparent surface of the sun or a star from which light appears to radiate.

In physics, nuclear fusion refers to the process in which two atomic nuclei come together to form a heavier nucleus,...

An instrument consisting essentially of a photoelectric cell filtered to respond to a specified wavelength region, an...

A handheld navigational instrument used to measure the elevation angle of celestial bodies such as the sun. An image of the...

Photovoltaic (PV) refers to a technology that converts sunlight directly into electricity using semiconductors. The term...

A solar simulator is a device used to replicate the spectrum and intensity of sunlight in a controlled environment for...

The term photochemical pertains to chemical processes or reactions that are initiated or influenced by the absorption of...

Phase shift in electromagnetic signals caused by daily variations in the ionosphere, often during sunrise or sunset.

A test used to measure the degree of fading of different colored materials, especially those involving organic dyes, which...

A device that measures the intensity of photochemically active radiation, particularly from the sun. One form of this...

The point of a planet or comet's orbit that is farthest from the sun.

The point to which the extension of the straight line, reaching from the sun to the observer's eye after penetrating the...

Radiation from the sun that is made up of a very wide range of wavelengths, from the long infrared to the short ultraviolet...

A compact high-pressure light source in which an electrical discharge between electrodes spaced no more than 12 mm apart...

Photochromic refers to a property exhibited by certain materials, typically organic compounds or dyes, which undergo...

A device having a plane mirror so mounted that it can be set to reflect sunlight into a piece of laboratory equipment. It is...

A dark band that may appear in the field of crossed Nicol prisms with a powerful source such as the sun because the light is...