Planets : The group of different characteristics of lands and atmospheres with different lives.

                

              While knowledge of the planets predates history and is common to most civilizations, the word planet dates back to ancient Greece. Most Greeks believed the Earth to be stationary and at the center of the universe in accordance with the geocentric model and that the objects in the sky, and indeed the sky itself, revolved around it (an exception was Aristarchus of Samos, who put forward an early version of heliocentrism).

                    Greek astronomers employed the term asters Plantae, "wandering stars”, to describe those starlike lights in the heavens that moved over the course of the year, in contrast to the asters alpines, the "fixed stars", which stayed motionless relative to one another. The five bodies currently called "planets" that were known to the Greeks were those visible to the naked eye: Mercury, Venus, Mars, Jupiter, and Saturn.