Cosmology is the study of the structure and formation of the universe.
Ancient and medieval cosmologists were common, usually oriented around a world view of a stationary, flat earth as the center of the universe. Aristarchus understood that the earth was spherical and circled the sun. With the increasing sophistication of observing techniques and equipment, a more modern understanding of the universe emerged.
Much of modern cosmology is atheistic, liberal pseudo or junk science which rejects God as explanations for the existence of the universe, instead relying on debunked theories such as relativity and the Big Bang theory based on the recession of galaxies shown by Red Shift all occuring in a time frame which predates creation. Some secular scientists also advocate the Steady state theory.
The New American Desk Encyclopedia, Penguin Group, 1989