Probable History And Origin: The significance of the Orientale basin extends beyond its great size. Orientale furnished information that helped to explain the probable origin of some, if not all, of the great lunar maria. It raised questions concerning the geologic history and evolution of the moon and of the earth as well. Statistically, the earth should have been struck by at least as many large meteoroids as the moon. Events such as the formation of the Orientale basin must have made significant contributions to the surface and near-surface development of the moon.
We have no positive information about an astrophysical quantity as fundamental as the amount of gas in the vast regions of space between the galaxies. This question has been considered, in theory at least, in somewhat different ways by astronomers whose concern has included theories of the probable history and origin of the universe. Proponents of one such theory-the "big-bang" theory-postulate that all the matter of the universe originated as the aftereffects of a single colossal explosion, and that the resulting expansion of galaxies outward into the distant regions of space is still going on. In contrast to the big-bang theory, there has also developed a less violent "steady-state" theory of creation.
The history of cultivated plants has received the attention of specialists who have searched historical records of the earliest writers of Egypt and China. Evidence has been adduced to trace places of origin and routes by which many trees, flowers, and vegetables were dispersed by human agency. In some instances information is precise, for example with regard to the cultivation of millet, lentils, onions, beans, peas and other vegetables in early Egypt, but the task of tracing the absolute origin and line of migration is almost impossible.
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