The spherical and spectral tracking position of a source, and its first and second time derivatives. More...

#include <novas.h>

Public Attributes
struct novas_observable	accel
	[deg/s²,AU/s²,1/s²] Apparent position acceleration.
struct novas_observable	pos
	[deg,AU,1] Apparent source position
struct novas_observable	rate
	[deg/s,AU/s,1/s] Apparent position rate of change
struct novas_timespec	time
	The astronomical time for which the track is calculated.

Detailed Description

The spherical and spectral tracking position of a source, and its first and second time derivatives.

As such, it may be useful for telescope drive control (position, velocity, and acceleration), or else for fast extrapolation of momentary positions without a full, and costly, recalculation of the positions at high rate over a suitable short period.