A Tale of Planetary Woe NASA

Once upon a time — roughly four billion years ago — Mars was warm and wet, much like Earth. Liquid water flowed on the Martian surface in long rivers that emptied into shallow seas. A thick atmosphere blanketed the planet and kept it warm. Living microbes might have even arisen, some scientists believe, starting Mars down the path toward becoming a second life-filled planet next door to our own.
But that’s not how things turned out.
Mars today is bitter cold and bone dry. The rivers and seas are long gone. Its atmosphere is thin and wispy, and if Martian microbes still exist, they’re probably eking out a meager existence somewhere beneath the dusty Martian soil.