Landing humans on Mars is a completely achievable feat with current technology—if you are okay with the idea of a one-way ticket, points out physicist and Scientific American columnist Lawrence Krauss in an op-ed in yesterday's New York Times .
The problem today isn't the launch capabilities or the guidance systems or the navigation. It is the energetic particles from the sun, which can rip apart DNA. Space travelers returning home from a Mars mission would soon die from this radiation poisoning, if they managed to survive the experience at all. A protective shield would simply be too massive to be practical; assuming no technological breakthroughs, the shield would weigh around 400 tons—much too massive for today's heavy-lift vehicles.
Krauss notes that a one-way trip would be more sensible. (But like most scientists, Krauss thinks that robots can accomplish as much as humans can in terms of doing actual science in space.) We could send senior-citizen volunteers to the Red Planet, where they could spend their final months conducting experiments, laying the groundwork for future permanent settlements, and digging their own graves.
The idea of a one-way trip has been kicked around for years. I first became aware of it some 10 years ago, when SciAm editor George Musser (currently installing solar panels on his home) brought it up at one of our story meetings. As our resident Mars-ophile, George said he would go once and for all, without hesitation—and he was the only one on staff at the time who would. An informal poll of 12 others on staff this morning revealed two other yays, albeit with the general qualification of not having much to live for on Earth.
As news editor, I would certainly appreciate having a Mars bureau, even if for just a couple of months. Imagine the tweets during a voyage of possibly 200-plus days in an enclosed environment with the same small group. Day 65: Main toilet is broken—again! Day 110: I should have smuggled more beer on board. Day 175: I can't believe I'm going to be buried with these people.
A round-trip Mars mission might be achievable, though—not with faster rockets, but with biomedical advances. Drugs that safely combat the effects of radiation poisoning seem to be the only way to make a voyage back home feasible, as Eugene N. Parker points out in an article in the March 2006 issue and in a Science Talk podcast interview.
Illustration of astronauts on Mars from NASA