The origins of astrophysics go back to antiquity. The first known civilizations observed and recorded the movements of celestial bodies like the stars, the planets, and the Moon. Since its inception, it was separated from the study of terrestrial physics, as it was understood to operate with different materials and dynamics. Plato (428-348 BC) theorized that the celestial region was essentially constituted by fire, while Aristotle (384-322 BC) thought that its main component was ether.
The development of astrophysics as a modern scientific discipline, however, began in the 19th century, when scientists like Isaac Newton and Johannes Kepler established the laws of gravitation and planetary motion. Since then, astrophysics has evolved and become highly specialized. Some of its applications include atomic and molecular astrophysics, bioastrophysics, stellar astrophysics, etc.