The pointing_object structure (a_pointing_object)

The pointing object structure is intended to contain data needed for pointing a telescope however this can generally be used to store information about the current position of the telescope, most programs should have two of the structures, one describing the telescopes position the other describing where the telescope should be pointed.

alt
A floating point number describing the altitude of the telescope in degrees if this is not reported or not used it should be set to -1.

az
A floating point number describing the telescopes azimuth position in degrees. If this is not in use its value should be set to -1.

ra
The right ascension of the telescope in decimal hours. If this data value is not in use it should be set to -1.

dec
The declination of the telescope in decimal degrees. If this data value is not being used it should be set to -1.

equinox
The equinox of the object coordinates in decimal years. This value is mandatory when using ra and/or dec however if using alt or az this value is ignored.

object_name
A character string that is the name of the object if not know set to NULL. This is not mandatory but the implementor is encouraged to use this string.

ppm
A floating point number indicating the objects proper motion in arcseconds per year.

epoch
The epoch of the coordinates, for precession and proper motion calculation.