photobiology (version 0.9.11)

sun_angles: Solar angles

Description

This function returns the solar angles for a given time and location.

Usage

sun_angles(time = lubridate::now(), geocode = NULL, lon = 0, lat = 0, use_refraction = FALSE)

Arguments

time

POSIXct Time, any valid time zone (TZ) is allowed, default is current time

geocode

data frame with variables lon and lat as numeric values (degrees).

lon

numeric Vector of longitudes (degrees) W is < 0, and E is > 0

lat

numeric Vector of latitudes (degrees)

use_refraction

logical Flag indicating whether to correct for fraction in the atmosphere

Value

A list with components time in same TZ as input, azimuth, elevation, diameter, and distance.

References

Michalsky, J. J., 1988. "The Astronomical Almanac's algorithm for approximate solar position (1950--2050)". Solar Energy, 227--235.

Spencer, J. W., 1989. "Comments on The Astronomical Almanac's algorithm for approximate solar position (1950--2050)." Solar Energy, 42, 353.

Vignola, F.; Michalsky, J. & Stoffel, T., 2012 (Eds.) "Solar and infrared radiation measurements." Boca Raton, CRC Press, ISBN 9781439851890.

See Also

Other astronomy related functions: day_night

Examples

require(lubridate)
sun_angles()
sun_angles(ymd_hms("2014-09-23 12:00:00"))
sun_angles(ymd_hms("2014-09-23 12:00:00"), lat=60, lon=0)