R: Solar astronomy using Meeus' algorithm

julian_day {photobiology} | R Documentation

## Solar astronomy using Meeus' algorithm

### Description

Low level functions based on NOAA's Excel 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_decline(app.lon, obliq.corr)

    var_y(obliq.corr)

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

    ha_sunrise(lat, decline, nag = 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, decline)

    elevation_angle(lat, hour.angle, decline)

    atm_refraction_approx(elevation.angle)

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

### Arguments

`time` | dateTime
`x` | numeric Julian century
`anom` | numeric Solar anomaly in degrees
`eccent` | numeric Eccentricity of Earth orbit
`eclip` | numeric Ecliptic
`app.lon, obliq.corr, mean.lon, nag, decline` | 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

[Package photobiology version 0.9.21 Index]