Last week, the White House announced that humans would aim to set foot on Mars by 2033, just sixteen years from now. As a longtime space lover, I found this news momentarily exciting, but then I paused. Is sixteen years in any way realistic? I think not.

Taking people to Mars – and back again – is a massive engineering problem, on a scale we have never before encountered. I believe it’s possible to do it, but if we try to rush it, it will end in calamity. It breaks down to a number of key problems:

Radiation

Without sufficient protection, astronauts will be subjected to intense radiation from the sun and from cosmic rays for the entirely of their journey. It goes without saying that space is a hostile environment, but, given the absence of a strong magnetic field, so too is Mars. We have very little experience of the effects of long term radiation exposure on humans outside of Earth, so a huge effort is required to gain more knowledge before we go. Frequent trips to or around the Moon would help, but given the absence of any such journeys in the last 40 years, we are starting practically from zero.

Supplies

A crew of people will need to be sheltered, protected, fed, oxygenated, medicated and kept warm for up to three years from start to finish. They will need to have all the equipment they need to do their jobs, plus replacements, if something goes wrong. This implies a support structure to be in place – around Mars, on the way to Mars, on the way back from Mars and possibly even on the surface of Mars itself – before the astronauts begin their journey. That’s a lot of work – much greater than anything encountered by the lunar astronauts. Of course a very large craft might be able to bring people and supplies along in one go, but getting all this out of Earth’s gravity well and into the International Space Station will be a challenge in its own right, not to mention landing so much of it on Mars.

Getting off the surface of Mars

Apart from the Moon, we have never attempted lifting equipment – not to mention people – from the surface of another planet. The Moon, with its weak gravity, is much more trivial a problem than Mars would be. Consider the problems here on Earth. We have yet to conquer routine space launches. They require months of preparation and testing with teams of engineers to execute. Costs per launch are still in the millions of dollars. And even then, things can go wrong: launches fail regularly or are scrubbed in the last few seconds. Now imagine having to do this on Mars, where a failure, no matter how small, might mean you are left on the planet for good. We need a lot of practice at this, on Mars, before we attempt to bring people along.

Leaving them there

Sure, we could forego return craft and find volunteers to go to Mars for good, but without any prior experience of living on Mars, my guess is that they would not survive there for long. We on Earth would be treated to a real-time Truman Show of suffering, sickness and eventual death. This would quickly wipe the shine off mankind’s’ great achievement.

Contamination

Right now, we still don’t know if life exists on Mars. Even though it’s unlikely, given the harshness of the Martian environment, it cannot be completely ruled out. Small traces of methane have been detected that deserve proper investigation. If we put humans on Mars – or god forbid, leave human corpses there – we lose our chance to find alien life there forever. We will have contaminated Mars with our own DNA, making any subsequent reports of life there highly suspect. We have the opportunity to make a truly extraordinary discovery on Mars. We owe it to ourselves to search hard for Martian life before we put boots there.

Let’s take our time

I get the feeling that this sixteen year trip to Mars is a kind of prestige project for Trump, as opposed to a genuine mission of science and discovery. I would love for us to visit Mars one day, but I think sixteen years is far too soon. We have a lot of learning to do and a lot of infrastructure to build before we can proceed with a manned mission that has a reasonable likelihood of success. Perhaps I’m pessimistic, but I think that the first successful landing is less likely to be sixteen years from now, and more likely to be sixty.