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photobiology (version 0.9.16)

julian_day: Solar astronomy using Meeus' algorithm

Description

Low level functions based on NOAA's Excell worksheet

Usage

julian_day(time)

julian_century(time)

geom_mean_lon_sun(x)

geom_mean_anom_sun(x)

eccent_earth_orbit(x)

sun_eq_of_ctr(x, anom)

sun_rad_vector(eccent, anom)

sun_app_lon(x, lon)

mean_obliq_eclip(x)

obliq_corr(x, eclip)

sun_rt_ascen(app.lon, obliq.corr)

sun_declin(app.lon, obliq.corr)

var_y(obliq.corr)

eq_of_time(mean.lon, eccent.earth, anom.mean, var.y)

ha_sunrise(lat, declin, ang = 0)

solar_noon(lon, eq.of.time)

sunrise(noon, ha.sunrise)

sunset(noon, ha.sunrise)

sunlight_duration(ha.sunrise, unit.out = "hours")

solar_datetime(time, lat, lon, eq.of.time)

solar_tod(time, lat, lon, eq.of.time)

hour_angle(solar.time)

zenith_angle(lat, hour.angle, declin)

elevation_angle(lat, hour.angle, declin)

atm_refraction_approx(elevation.angle)

azimuth_angle(lat, hour.angle, zenith.angle, declin)

Arguments

time

dateTime

x

numeric Julian century

anom

numeric Solar anomaly in degrees

eccent

numric Eccentricity of Earth orbit

eclip

numeric Ecliptic

app.lon, obliq.corr, mean.lon, ang, declin

numeric Angles in degrees

lat, lon

numeric Geographic coordinates in degrees

eq.of.time, ha.sunrise, noon

numeric

zenith.angle, elevation.angle, hour.angle

numeric Angles in degrees

Value

datetime

numeric