Stars and planets, along with other celestial bodies such as moons, comets, and asteroids, are collectively known as astronomical objects or celestial objects. In astronomy, these objects are studied to understand the universe's composition, structure, and evolution. Stars are massive celestial bodies that produce light and heat through nuclear fusion, while planets are smaller bodies that orbit stars. The study of these objects encompasses a wide variety of fields, including astrophysics and cosmology, and helps scientists uncover the mysteries of the cosmos and our place within it.