*smacks head with a fallen dreg* Look..... Mars has a thin atmosphere okay? Do you know what that means? That means that most elements, like water, when cycled to a gaseous state will most of the time just leave the planet all together, also BECAUSE it has an atmosphere, it can retain wind currents that generate the massive planetary sandstorms that last from a week to a month. So without the terra formation by the traveler, Mars reverted back to its original state So stop whatever this is and go to school and learn this from whatever single digit grade term you learn this from cause I forgot.