astrometric binaries

Astrometric binaries are systems where two stars orbit each other, but we can only see one of them directly. The invisible companion's gravity affects the visible star's position, causing it to move slightly in a way that reveals its presence. By studying these subtle changes in position over time, astronomers can estimate the mass and orbit of the unseen star. This method helps enhance our understanding of stars and their interactions in the universe, as well as contributes to our knowledge about the distribution of mass in galaxies.