co_refract_forward:
Calculate the true altitude of a celestial object from an observed altitude.
Description
Calculate the true altitude of a celestial object from an observed altitude.
This function is called by co_refract, the function to correct altitude due to atmospheric refraction.
Usage
co_refract_forward(a, p = 1010, t = 283)
Arguments
a
The observed (`apparent') altitude, in degrees
p
Atmospheric pressure, in millibars (default=1010)
t
Ground temperature, in degrees Celsius (default=0)
Value
R
Correction to apparent altitude, subtracted from a, in degrees