The most intense wavelength emitted by an object is determined by its temperature . This relationship is known as Wien s Law. Wien s law shows that as the temperature of an object increases, the maximum wavelength of the radiated energy decreases. Because the maximum wavelength emitted by the sun is longer than that emitted by the earth, radiation emitted by the sun is often called shortwave radiation, whereas radiation emitted by the earth is called longwave radiation. The intensity of the radiation emitted by an object is determined by its temperature.
Hot objects emit more energy than cold objects.
The solar constant is the amount of solar radiation that reaches the top of the earth s atmosphere. Since solar radiation is emitted by the sun in all directions, the amount that reaches the surface of the earth is greatly reduced because of the distance between the sun and the earth.