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oce (version 0.9-18)

equatorialToLocalHorizontal: Convert equatorial to local horizontal coordinate

Description

Convert from equatorial coordinates to local horizontal coordinates, i.e. azimuth and altitude.

Usage

equatorialToLocalHorizontal(rightAscension, declination, t, longitude, latitude)

Arguments

rightAscension
right ascension, e.g. calculated with eclipticalToEquatorial.
declination
declination, e.g. calculated with eclipticalToEquatorial.
t
time of observation.
longitude
longitude of observation, positive in eastern hemisphere.
latitude
latitude of observation, positive in northern hemisphere.

Value

  • A data frame containing columns altitude (angle above horizon, in degrees) and azimuth (angle anticlockwise from south, in degrees).

Details

The method is taken from equations 8.5 and 8.6 of [1], or, equivalently, from equations 12.5 and 12.6 of [2].

References

1. Meeus, Jean, 1982. Astronomical formuae for Calculators. Willmann-Bell. Richmond VA, USA. 201 pages.

2. Meeus, Jean, 1991. Astronomical algorithms. Willmann-Bell, Richmond VA, USA. 429 pages.