Astronomy

n. study of celestial bodies (stars, planets, etc.)

Astronomy is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earth's atmosphere (such as the cosmic background radiation). It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe.
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Noun
1. the branch of physics that studies celestial bodies and the universe as a whole
(synonym) uranology
(hypernym) physics, physical science, natural philosophy
(hyponym) astrodynamics
(class) active

(n.)
The science which treats of the celestial bodies, of their magnitudes, motions, distances, periods of revolution, eclipses, constitution, physical condition, and of the causes of their various phenomena.
  

(n.)
Astrology.
  

(n.)
A treatise on, or text-book of, the science.
  

The generic name for the study of the universe around us. Traditionally astronomy was concerned with mapping the heavens and understanding how the the celestial objects moved. It is this early publishing of observations of the simple motions and then the development of Newton's Law of Gravity and thus the definite establishment of mass as a physical property (as important as length and time), that greatly assisted the development of the Modern Scientific era. The focus has now switched to astrophysics, which concerns itself with why things in the universe behave as they do.