Finding “absolute” parallaxes directly
نویسنده
چکیده
We develop the formalism for estimating parallaxes, proper motions and positions from long-focus astrometric observations as well as additional extraneous reference material whenever this is available and relax the constraints on the star parameters (basically their sums and correlations with the coordinates on the frames), thus generating (albeit correlated) quasiobservations whose inclusion would make the solutions determinate even if there were no extraneous reference material. The result are data on the same system to which the reference material is referred, so that there is no need to perform the “reduction from relative to absolute” as an afterthought.
منابع مشابه
Bias in Absolute Magnitude Determination from Parallaxes
Relations are given for the correction of bias when mean absolute magnitudes are derived by the method of reduced parallaxes. The bias in the case of the derivation of the absolute magnitudes of individual objects is also considered.
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