The exact julian day computation is adapted from ode::julianDay() and tested againts test cases in Redas and Andreas (2008, table A4.1) for validity up to year 4712 BC.
calendar_changejulian_day(time)
julian_day_fast(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)
dateTime
numeric Julian century
numeric Solar anomaly in degrees
numeric Eccentricity of Earth orbit
numeric Ecliptic
numeric Angles in degrees
numeric Geographic coordinates in degrees
numeric
numeric Angles in degrees
datetime
numeric
An object of class POSIXct (inherits from POSIXt) of length 1.
Low level functions based on NOAA's Excel worksheet