What is the primary limitation when detecting an astrometric binary?

Answer

It requires high-precision tracking over a long period

An astrometric binary is detected by observing the 'wobble' of a visible star, which is caused by the gravitational influence of an unseen companion. The main challenge with this detection method is that it requires high-precision tracking of the star's position over a significant amount of time to confirm that the motion is due to an orbital companion rather than other factors.

What is the primary limitation when detecting an astrometric binary?
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