relative astrometry

Relative astrometry is a technique used in astronomy to measure the positions and movements of celestial objects in relation to one another, rather than against a fixed background like distant stars. By tracking how these objects shift over time, scientists can learn about their distances, orbits, and physical properties. This method is important for studying planets, moons, and other bodies in our solar system, as well as stars in binary systems. It helps astronomers understand the dynamics of these objects and can reveal details about their mass and composition.