Solar zenith angle minutes of arc, which is less than the apparent angular radius of the sun. The formula also neglects the effect of atmospheric refraction. Sunset and sunrise occur (approximately) when the zenith angle is 90°, where the hour angle "h" satisfies Precise times of sunset and sunrise occur when the upper limb of the Sun appears, as refracted by the atmosphere, to be on the horizon. A weighted daily average zenith angle, used in computing the local albedo of the Earth, is given by where "Q" is the instantaneous insolation. For example, the solar elevation angle is : An exact calculation
Less-than sign encoded as a single-byte code point token. In Fortran, operator .LE. means "less than or equal to". In Bourne shell and Windows PowerShell, the operator -le means "less than or equal to". In the R programming language, the less-than sign is used in conjunction with a hyphen-minus to create an arrow (codice_1), this can be used as the left assignment operator. In Bourne shell (and many other shells), less-than sign is used to redirect input from a file. Less-than plus ampersand (<&) is used to redirect from a file descriptor. Less-than sign is used in the spaceship operator. In HTML