Astrometry focuses on precisely measuring the positions, distances, and motions of celestial objects in the sky.

Telescopes, equipped with specialized instruments, are used to accurately measure the positions of stars and other celestial objects.

The equatorial coordinate system is the standard reference frame used in astrometry to define the positions of stars and other celestial objects.

Parallax is the apparent shift in the position of a star as seen from different points on Earth's orbit around the Sun.

Trigonometric parallax is the method used to measure the distances to nearby stars by measuring the angle between their positions from two different points on Earth's orbit.

Precession is the gradual shift in the orientation of Earth's axis over time, causing the positions of stars to change slowly over centuries.

Astrometry involves measuring the proper motions of stars, which are their actual motions through space, to study their kinematics and dynamics.

Gaia is a European Space Agency mission designed to measure the positions, distances, and motions of billions of stars in our galaxy with high precision.

Interferometry is an astrometric technique that combines the light from multiple telescopes to achieve higher resolution and sensitivity, allowing astronomers to detect binary star systems and measure their orbital parameters.

Diurnal aberration is the apparent change in the position of a star due to the Earth's rotation, causing stars to appear slightly displaced from their true positions.

Astrometry can be used to detect and characterize exoplanets by measuring the slight wobbles in the positions of stars caused by the gravitational pull of orbiting planets.

Nutation is the phenomenon that causes the positions of stars to appear to move in a small circle over time due to the periodic changes in the orientation of Earth's axis.

Astrometry can be used to study the structure and dynamics of our galaxy by measuring the positions and motions of stars, providing insights into the Milky Way's shape, rotation, and mass distribution.

Annual aberration is the apparent change in the position of a star due to the Earth's orbital motion around the Sun, causing stars to appear slightly displaced from their true positions.

Astrometry can be used to detect and study double star systems by measuring the slight variations in the positions of stars over time, caused by their mutual gravitational interaction.