In 1784, the famous astronomer William Herschel once wrote that the dark areas on the surface of Mars are oceans, and the brighter areas are land  Herschel speculated that there must be intelligent life on Mars, and they may be similar to us on Earth
Where there is sea and land, there must be intelligent life
 Herschel's theory has been popular for more than a century, and even some other astronomers have echoed that vegetation can be observed in some brightly colored areas