What is Astronomy?
the study of everything in the universe beyond Earth's atmosphere
Astronomy (from Ancient Greek ἀστρονομία (astronomía) 'science that
studies the laws of the stars') is a natural science that studies
celestial objects and phenomena. It uses mathematics, physics, and
chemistry in order to explain their origin and evolution. Objects of
interest include planets, moons, stars, nebulae, galaxies, and comets.
Relevant phenomena include supernova explosions, gamma ray bursts,
quasars, blazars, pulsars, and cosmic microwave background radiation.
More generally, astronomy studies everything that originates beyond
Earth's atmosphere. Cosmology is a branch of astronomy that studies the
universe as a whole.
Learn more about astronomy on wikipedia