skyscapeR (version 1.0.0)

jS: Declination of June Solstice for a given year

Description

This function calculates the declination of the sun at June Solstice for a given year, based upon obliquity estimation and corrected average parallax.

Usage

jS(
  year = skyscapeR.env$cur.year,
  loc = FALSE,
  parallax = 0.00224,
  altitude = 0,
  verbose = TRUE
)

Arguments

year

Year for which to calculate the declination. Defaults to present year as given by Sys.Date.

loc

(Optional) This can be either the latitude of the location, or a skyscapeR.horizon object. If missing or FALSE, function will output geocentric declination.

parallax

(Optional) Average parallax value for the sun. Defaults to 0.00224.

altitude

(Optional) Altitude of the sun. Defaults to 0 degrees.

verbose

(Optional) Boolean to control output of warnings and messages. Defaults to TRUE.

See Also

obliquity, dS, eq, zenith, antizenith, spatial.equinox, parallax.corr

Examples

# NOT RUN {
# June Solstice geocentric declination for year 4001 BC:
jS(-4000)

# Topocentric declination for same year and latitude of 50 degres N:
jS(-4000, loc=50)
# }