Wherever NASA is directed to go by the new administration will likely require a commitment that pushes the alternative back by decades. There’s simply no money in the NASA budget for both the moon and Mars. As the ISS demonstrated, building the thing—moon base or Mars colony—is the cheap part. It’s the operational costs that bog exploration down. Twenty percent of NASA’s budget goes to keeping the space station crewed and in orbit. A moon base will entail a similar such slice of the pie, which covers things like maintenance, ground support, technicians, engineers, physicians, launches, hardware, supplies, and food. You don’t maintain a moon base and gear up for Mars. Just the opposite: Going to Mars would specifically entail closing the moon base, which places Mars on the other side of lunar exploration, base design, base construction, base operations, base maintenance, and base divestment. NASA and world partners began work on the International Space Station began during Ronald Reagan’s first term. If we build a moon village, we’ll be there for a very long time.

Casey Dreier maintains that there is no correct destination for human spaceflight. “To me,” he says, “the least interesting argument in space exploration is ‘moon or Mars.’ It’s an important decision, but not an interesting argument. Mars is not objectively the only answer. The fundamental issue at play is what do we do that pays dividends as nation.” What dividends should we look for? Elon Musk advocates Mars colonization by defining Mars as humanity’s failsafe—that once we settle and flourish on a second world, no matter what catastrophe might befall Earth, be it an asteroid or atomic devastation, the human species can survive. NASA frames Mars exploration in more hopeful terms, calling it a scientific endeavor through which we can learn about the evolution Earth and life. Either way, those are enticing and worthy goals. Astronauts can press boot prints into Martian soil in less than 20 years, but for that to happen, NASA must stay the course.