Cosmology
Cosmology, study of the universe as a whole, including its distant past and its future. Cosmologists study the universe observationally—by looking at the universe—and theoretically—by using physical laws and theories to predict how the universe should behave. Cosmology is a branch of astronomy , but the observational and theoretical techniques used by cosmologists involve a wide range of other sciences, such as physics and chemistry. Cosmology is distinguished from cosmogony, which used to mean the study of the origin of the universe but now usually refers only to the study of the origin of the solar system.