Human bodies are optimized for life on Earth, and ill-equipped for environments like those we will find on Mars. But here at home there are organisms that do thrive in the extremes: the coldest, hottest, driest, and saltiest places. As gene editing technologies like CRISPR enable us to rewrite our own DNA, there may be adaptive tools we can borrow from these extremophiles. But while we are absorbed in self-preservation, it will be easy to neglect the planet we hope to colonize. After all, humans do not have the best track record when it comes to ethical exploration. While there is no evidence for life on Mars—yet—there is the matter of an entire land that has no one to speak for it, or to defend it. So in the process of getting humans to Mars, what values may be compromised along the way?