Abyssal plains were not recognized as distinct physiographic features of the sea floor until the late 1940s and, until very recently, none had been studied on a systematic basis. They are poorly preserved in the sedimentary record, because they tend to be consumed by the subduction process.
The first man to discover that the earth moves around the sun was an Italian scientist named Galileo Galilei.
The Significance of Kepler's Laws. Kepler's laws describe the motion of planets around the Sun. Kepler knew 6 planets: Earth, Venus, Mercury, Mars, Jupiter and Saturn. All these (also the Moon) move in nearly the same flat plane (section #2 in Stargazers).