Hello everyone, I kindly ask for your feedback on the following approach!
What I need
I would like to perform Batch Least Squares Orbit Determination of an object, given spacebased observations.
What I know
 Right Ascension / Declination measurements of a space object, from a spacebased telescope
 Measurement uncertainty expressed in ra / dec respectively
 Position vector of the spacebased telescope at each observation time, expressed in J2000.
What I would like to confirm

Since the uncertainty is expressed in ra/dec terms, I feel it makes sense to use
AngularRaDec
to add the measurements (subject to your critical review). 
In my effort to add
AngularRaDec
measurements, I notice that the constructor requires aGroundStation
location, but my telescope is not fixed to the ground!
Considering that:

GroundStation
instanciates with aTopocentricFrame
, and 
TopocentricFrame
implementsPVCoordinatesProvider
Is there any problem with assuming that my spacebased telescope is momentarily fixed in ITRF, and use the J2000toITRF position of my observer to define a “fake” GroundStation (geodetic point) for every measurement, as the location of my space telescope?
As I understand, an alternative way would be to define a new Measurement type, very similar to AngularRaDec
, but for spacebased measurements, according to this thorough explanation by Luc.
Thank you deeply in advance!
Manny