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astrometry




The precise measurement of the position of astronomical objects. Astrometrical observation of nearby stars, for example, is one of the techniques used to search for the presence of unseen companions, such as extrasolar planets, low-luminosity stars, and brown dwarfs. The gravitational influence of the unseen companion causes the path of the primary to wobble slightly, instead of following a smooth trajectory across the sky.


Related category

   • OBSERVATIONAL ASTRONOMY