Introduction to Astronomy

             The branch of science that deals with celestial objects, space, and the physical universe as s whole is called Astronomy. Astronomy is one of the oldest sciences. The invention of telescope was a prerequisite for astronomy to be ableto develop into a modern science. Historically, astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calenders, but professional astronomy is nowadays often considered to be synonymous with astrophysics. In astronomy the main source of information about celestial bodies and other objects is the visible light or more generally electromagnetic radiation. Dark matter and dark energy are the currently the leading topics in astronomy, as their discovery and controversy originated during the study of the galaxies.