# where is the solar constant measured

Solar constant, the total radiation energy received from the Sun per unit of time per unit of area on a theoretical surface perpendicular to the Sun’s rays and at Earth’s mean distance from the Sun. The blue region is from a model that is based on observations of stars such as the Sun, and the purple region is based on the effect of the solar magnetic flux on bright regions called faculae. Meaning of solar constant. …its radiative output, called the solar constant, is 1.366 kilowatts per square metre at Earth and varies by no more than 0.1 percent. The value of the constant is approximately 1.366 kilowatts per square metre. Articles from Britannica Encyclopedias for elementary and high school students. It is most accurately measured from satellites where atmospheric effects are absent. Superposed on this stable star, however, is an interesting 11-year cycle of magnetic activity manifested by regions of transient strong magnetic fields called sunspots.…, …and time—a value called the solar constant.…. (D) in the terrestrial region. 1367.5 1368. The solar constant includes all types of solar radiation, not just the visible light. It is most accurately measured from satellites where atmospheric effects are absent. Let us know if you have suggestions to improve this article (requires login). The solar energy absorbed by the earth is measured by the . Professor of Astrophysics, Emeritus; Director and Builder, Big Bear Solar Observatory, California Institute of Technology, Pasadena. The solar constant is calculated by multiplying the sun's surface irradiance by the square of the radius of the sun over the average distance between the Earth and the sun. Professor of Astrophysics, Emeritus; Director and Builder, Big Bear Solar Observatory, California Institute of Technology, Pasadena. For the best answers, search on this site https://shorturl.im/avxsF. "The solar constant is the amount of incoming solar electromagnetic radiation per unit area, measured on the outer surface of Earth's atmosphere in a plane perpendicular to the rays." 1 0. We then multiply the area by the insolation (in units of energy flow per unit area) to find out the total amount of incoming energy. 1370. (C) in the extraterrestrial region. The results of its measurement … The total solar intensity was 136.1 milliwatts per square centimeter, or 1.952 calories per square centimeter, per minute--about 2.5 percent less than Johnson's derived value. The solar constant is the amount of solar radiation incidence that is received at a distance of 1 astronomical unit (AU) from the Sun. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica. An astronomical unit (abbreviated as AU, au, a.u., or ua) is a unit of length equal to exactly 149,597,870,700 metres (92,955,807.273 mi) or approximately the mean Earth–Sun distance. The short-wavelength radiation reaching on the Earth is (A) 0.03 to 0.30 μm (B) 3 to 30 μm (C) 0.3 to 3 μm (D) None of these. What does solar constant mean? Now, the solar constant is also measured in terms of Wm 2, or watt per square meter. Lv 4. Superposed on this stable star, however, is an interesting 11-year cycle of magnetic activity manifested by regions of transient strong magnetic fields called sunspots.…, …and time—a value called the solar constant.…. Solar constant The solar constant is the amount of incoming solar electromagnetic radiation per unit area, measured on the outer surface of Earth's atmosphere in a plane perpendicular to the rays. 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