What is Earth symbol?

A variety of symbols or iconographic conventions are used to represent Earth, whether in the sense of planet Earth, or the inhabited world, or as a classical element. A circle representing the round world, with the rivers of Garden of Eden separating the four corners of the world, or rotated 45° to suggest the four continents, remains a common pictographic convention to express the notion of "worldwide". The current astronomical symbol for the planet is a circle with an intersecting cross,. Although the International Astronomical Union now discourages the use of planetary symbols, this is an exception, being used in abbreviations such as M? for Earth mass.