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The year is 2066. The sun rises dimly in a rust-coloured sky, lighting up the hydroponic fields. In the first permanent habitat on Mars, intrepid explorers are waking up to start another 24.5-hour day.

Elon Musk thinks it鈥檚 possible. In September, the SpaceX founder unveiled his (still somewhat vague) plan for sending humans to Mars in the next decade or so, and suggested that we might have a million people living full-time on the Red Planet by the 2060s. NASA鈥檚 more conservative plan sees the first humans going there in the 2030s.

We鈥檒l have to get moving. Before settlers can start building a life, we would need to set up everything they need to merely survive on the surface. This means launching tonnes of life-support equipment, habitats, energy-generation systems, food, and technology for extracting breathable oxygen and drinkable water from the air.

That鈥檚 a huge challenge. The shortest journey time between Earth and Mars is roughly five months, but that would only be possible around once every two years when the planets align with one another. In the most optimistic scenario, this gives us about 22 ideal launch opportunities to lay the groundwork for human settlement by 2060.

And as the recent failure of the ExoMars lander (right) shows, landing on Mars is tricky: it has enough gravity to accelerate a craft鈥檚 descent, but such a thin atmosphere that parachutes won鈥檛 slow it down enough. The heaviest thing that ever landed on Mars, the 1-tonne Curiosity rover, used a combination of parachutes, retrorockets and a daredevil dangling device called a sky crane.

Given that we don鈥檛 know how to land a mass heavier than that on the surface, planners have their work cut out. SpaceX plans to use a technique called supersonic retro-propulsion 鈥� basically reversing down with the booster rocket firing to slow the descent 鈥� and hopes to test the system in 2018. NASA has agreed to help with the project, in exchange for access to some of what we learn from it.

That鈥檚 not to mention the hazards of the journey and after landing. These include high levels of radiation, the threat of solar flares, dust that covers solar panels and could rip through lungs like shards of glass, and temperatures as low as -125 掳C. And we don鈥檛 know how to grow food there.

But let鈥檚 assume we overcome all these challenges. Then what? Fans of space exploration like to point out that humans have set off from their homes in search of a new life somewhere remote and possibly dangerous many times. Getting on a boat for the New World often meant you would never see your home or family again.

What鈥檚 different about Mars is that there is nothing to do there except try not to die. When European explorers struck out for the Americas, they hoped to find resources that they could sell back to their homeland, or at least a spot to establish a farm. Mars has few resources. The first settlers will be dependent on the home world for a very long time. Self-sufficiency by 2060 seems very ambitious.

One thing that settlers could usefully do, though, is science. A human could do research in an hour that takes a Mars rover months. And, of course, research on growing food would take on much more urgency.

We do have a model for such a remote yet invaluable research outpost: Antarctica. No one lives there permanently, but people make sojourns lasting a year or two to do science that is not possible anywhere else. Mars could be similar.

Another difference from past expansions into terra incognita is that Mars settlers will be in constant communication with Earth, albeit delayed a few minutes by the limits of light speed. Those of us still on Earth will almost certainly watch their lives unfold. We will see everything that goes right, and everything that goes wrong.

Whether we push further into the solar system or retreat back to Earth will probably depend on the balance of those two things. If we figure out how to get food and air and a way of living on the Red Planet, it seems likely that we could adapt those ideas for other planets or, more probably, moons. Mars will be the first big test of whether we can become a multiplanetary species.

This article appeared in print under the headline 鈥淲hat if鈥� we put a colony on Mars?鈥�