solar constant

noun

1. the average rate at which radiant energy is received from the sun by the earth, equal to 1.94 small calories per minute per square centimeter of area perpendicular to the sun's rays, measured at a point outside the earth's atmosphere when the earth is at its mean distance from the sun.

solar constant

noun

1. the rate at which the sun's energy is received per unit area at the top of the earth's atmosphere when the sun is at its mean distance from the earth and atmospheric absorption has been corrected for. Its value is 1367 watts per square metre

solar constant

1. The average amount of solar radiation received by the Earth's atmosphere, per unit area, when the Earth is at its mean distance from the Sun. It is equal to 1370 watts per square meter. Solar radiation varies with the Earth's distance from the Sun and with the appearance or decay of sunspots.

Word History and Origins

Origin of solar constant¹

First recorded in 1865–70

Example Sentences

The Platform could make much more precise measurements of the solar constant than could be obtained below.

From Project Gutenberg

Its summit elevation is nearly 15,000 feet, and in 1881 Langley made its ascent for the purpose of measuring the solar constant.

From Project Gutenberg