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
Craters of the Moon National Monument and Preserve A series of newspaper and magazine articles written by Limbert were later published about this and previous treks, which increased public awareness of the area. The most famous of these was an article that appeared in a 1924 issue of "National Geographic" where he called the area "Craters of the Moon," helping to solidify the use of that name. In the article he had this to say about the cobalt blue of the Blue Dragon Flows: In large part due to Limbert's work, Craters of the Moon National Monument was proclaimed on May 2, 1924 by U.S. President Calvin Coolidge