What is Astronomy?
Astronomy is a natural science. It is the study of everything outside the atmosphere of Earth.
It studies celestial objects (such as stars, galaxies, planets, moons, asteroids, comet sand nebulae) and processes (such as supernovae explosions, gamma ray bursts, and cosmic microwave background radiation). This includes the physics, chemistry of those objects and processes.
The word astronomy comes from the Greek words astron which means star and nomos which means law. A person who studies astronomy is called an astronomer.
The heavens declare the glory of God; the skies proclaim the work of his hands. Day after day they pour forth speech; night after night they reveal knowledge. They have no speech, they use no words; no sound is heard from them.