The detailed study of the stars, planets, galaxies, and comets, is applied in the understanding of the cosmic background radiation that takes place consistently beyond the atmosphere of the Earth. The revelations have largely affected and influenced man's understanding of evolution, meteorology, and the laws of physics. The movements observed have enabled scientists to gain a deeper understanding of the celestial objects as part of and the origin of the development of the universe. In fact, astronomy is one of the oldest sciences applied! Earlier, astronomers were very methodical in approach of their observations of the night sky. This observation-based science was only able to develop into the modern science it is today, after the invention of the telescope.
Astronomy includes the combination of other disciplines such as celestial navigation, astrometry, observational astronomy, and astrology. However, recent research declares the science of professional astronomy to be synonymous with that of astrophysics. Professional astronomy is studied under the theoretical and observational branches. While its observational branch focuses on the collection and analysis of data, the theoretical branch involves the development of analytical models, to better describe the various astronomical objects and phenomena sighted. The two branches of this exquisite bailiwick are used in combination to explain the observations and confirm theoretical results.
Astronomy, for beginners, is an amazing sphere to explore, especially considering the fact that a number of amateurs have contributed squarely to many astronomical discoveries. It is also believed to be one of the few sciences where amateurs play an active role! This springs from the fact that their recorded data helps a lot in the discovery and observation of transient celestial phenomena. Astronomy and astrology have two commonalities; both observe the positions of celestial objects and share a common origin. Besides this, the use of ephemerides in either is distinct.
In quondam times, this area of study included observations to predict motions of objects visible to the naked eye, determine the seasons, and understand the length of the year. Before the invention of the telescope, the study of stars was possible only from vantage points like tall buildings and the tops of trees! In time, as civilizations developed, astronomical observatories were established. With the intent of exploring the nature of the universe, early astronomy comprised mapping the positions of the celestial objects. This was the humble beginning of the science of astrometry. This mapping formed the earliest observations of inter-planetary motion and the philosophical nature of the Sun, Moon and the Earth.
Previously, the Earth was believed to be the center of the universe and was studied as the 'geocentric model' of the universe. However, the myth was broken by a number of astronomical discoveries, like the 'obliquity of the ecliptic', 'lunar eclipses', and the size and distance of Earth's natural satellite, the Moon. All this was even before the telescope was invented. The subject includes the acknowledgement of the work of scientists like Galileo, Copernicus, and Kepler. Their detailed sketches and observations of the celestial bodies have been defended, expanded upon, and corrected over the years.
It also includes the understanding of the discoveries and paralleled improvements in the size and quality of the various telescopes. The study involves the understanding of the extensive star catalogs nebulosity and clusters, the discoveries of new planets, distances between stars, and development of more accurate predictions about the motions of the celestial bodies. Amateurs must also study, observe, and understand, the calculations of the masses of the celestial bodies, estimated from their perturbations, and the significant advances in astronomy due to the introduction of instruments like the spectroscope.
The initial study includes the calculations of the varying temperatures and sizes of celestial bodies, the study of the existence of the Milky Way as a separate group of stars, and the discovery of the many exotic objects like blazers, quasars, etc.