Astronomical catalogs are collections of data and information about celestial objects such as stars, galaxies, and other astronomical phenomena. These catalogs typically include characteristics such as position, brightness, distance, and spectral characteristics of the objects. They can also contain data on observations, classifications, and properties of astronomical objects, often compiled from observations made with telescopes and other instruments. Astronomical catalogs are important tools for astronomers studying the cosmos, as they provide a comprehensive database of information that can be used to study the distribution and properties of celestial objects in the universe.