According to new research presented at the annual Goldschmidt geochemistry conference in Florence, there is compelling evidence that life on Earth was kick-started by a meteorite from Mars bearing simple, RNA-based organisms. Furthermore, the same research also indicates that the ancient, primordial surface of Earth would've been inhospitable to the formation of the building blocks of life (RNA, DNA, and proteins) -- therefore, the only way that life could've begun more than three billion years ago is if it arrived here from Mars.