Convert from equatorial coordinates to local horizontal coordinates, i.e. azimuth and altitude. The method is taken from equations 8.5 and 8.6 of [1], or, equivalently, from equations 12.5 and 12.6 of [2].
equatorialToLocalHorizontal(rightAscension, declination, t, longitude,
latitude)right ascension, e.g. calculated with
eclipticalToEquatorial.
declination, e.g. calculated with
eclipticalToEquatorial.
time of observation.
longitude of observation, positive in eastern hemisphere.
latitude of observation, positive in northern hemisphere.
A data frame containing columns altitude (angle above
horizon, in degrees) and azimuth (angle anticlockwise from south, in
degrees).
1. Meeus, Jean, 1982. Astronomical formulae for Calculators. Willmann-Bell. Richmond VA, USA. 201 pages.
2. Meeus, Jean, 1991. Astronomical algorithms. Willmann-Bell, Richmond VA, USA. 429 pages.
Other things related to astronomy: eclipticalToEquatorial,
julianCenturyAnomaly,
julianDay, moonAngle,
siderealTime, sunAngle