Exploration of the Moon invention of the telescope, an increasing number of people began to recognise the Moon as a sphere, though many believed that it was "perfectly smooth". In 1609, Galileo Galilei drew one of the first telescopic drawings of the Moon in his book and noted that it was not smooth but had mountains and craters. Later in the 17th century, Giovanni Battista Riccioli and Francesco Maria Grimaldi drew a map of the Moon and gave many craters the names they still have today. On maps, the dark parts of the Moon's surface were called "maria" (singular "mare") or seas, and the
Ghost craters on Mercury Mars do not have both tectonic features within their ghost craters, possibly due to the accumulation rates of volcanic material on the Moon and Mars being slower than the rates on Mercury. Ghost craters on Mercury Ghost craters on the planet Mercury have tectonic features such as graben and wrinkle ridges. These features were formed by extensional and contractional forces originating in tectonic processes such as uplift and global contraction. The combination of graben and wrinkle ridges inside ghost craters found on Mercury has not been observed on any of the other terrestrial planets. The tectonic features on Mercury were