What does astronomy study?

Astronomy is the scientific study of celestial objects, space, and the universe as a whole. This field encompasses the observation and analysis of various celestial bodies, including stars, planets, moons, galaxies, and the phenomena that occur in the universe. By studying the moon, stars, and other celestial objects, astronomers can gain insights into the origins and evolution of the universe, the life cycles of different astronomical entities, and the laws governing their movements and interactions.

The other choices highlight areas of study that fall outside the realm of astronomy. The structure of Earth's layers is part of geology, chemical reactions in a laboratory pertain to chemistry, and the physical movements of Earth relate to geophysics or Earth science. Each of these fields focuses on different aspects of natural science, whereas astronomy specifically targets the vast expanses and components of the cosmos.