For thousands of years, humans have looked up at the night sky and pondered their place in the cosmos. One little red dot in particular has long held their interest: Mars. Today, experts believe it’s no longer a question of if we’ll ever set foot on the Red Planet, but when. Recent technological advances mean this could happen within a few decades.

While the dream of colonizing Mars is a fascinating one, is it really a good idea? What will be the biggest challenges? And once we get there, could we even survive?

The biggest incentive for putting humans on Mars is to have “an insurance mechanism for our species,” says Stephen Petranek, author of How We’ll Live on Mars. “We’re a nomadic species. We learned long ago that if we don’t move, we don’t survive… [and we’ll] have to move out of our solar system when our sun dies.” That is a solid if somewhat depressing point. Mars is the closest place for us to practice for that eventuality.”

Mars was almost identical to Earth roughly four billion years ago. Today, it remains the only planet in our solar system that’s closest in similiarity to Earth, to even possibly sustain human life. It’s half the size of our pale blue dot, but has the same amount of land, which means we’d have a place to settle and flourish. The temperature on Mars is frigid, but its ice means we’d have a water source. The planet’s oxidized soil means we could grow food, and the existence of methane gas means we could create fuel.

If getting to Mars is the biggest hope for saving human civilization, then our next step is to create the technology to do it.

“The first pioneers are already on Mars,” Dr. Ashwin R. Vasavada, MSL-Curiosity project scientist, told The Week. Of course, he’s not talking about people; he’s talking about robots like the Curiosity rover that photograph and analyze Mars every day. Those robots are doing the prep work for Mars’ first human explorers.

 

A new study published in the journal Scientific Reports found that even six months after returning to Earth, Mars astronauts would experience brain inflammation and neuron damage. Other side effects of long-term space travel could include memory problems, anxiety, and depression. The study concludes with a dire warning: “Cosmic radiation exposure poses a real and potentially detrimental neurocognitive risk for prolonged deep space travel… [and] deep space travel poses a real and unique threat to the integrity of neural circuits in the brain.”

So, given these dangers, should we even bother with Mars? NASA remains hopeful. “This risk is felt to be manageable,” says Richard Davis, assistant director for science and exploration in NASA’s Planetary Science Division. “As we have done with all human space flight to date, we will proactively study potential impacts to our crewmembers from this radiation as they travel to, live, and explore on Mars, and will develop additional countermeasures, as needed.”