What are the prospects for manned missions?

DW: It was in 1972 that man for the last time set foot on the moon. Why should we actually go back? Just because the Chinese want to go up there?

Thomas Reiter: There are still a lot of things to learn on the moon. It's basically a history book of our own planet. The regions that were visited in those days were geologically not so interesting. Now we are focusing more on the polar regions. We still need to develop technologies because all this knowledge of the 1960s and the beginning of the 70s is gone. And therefore, it's good to go back.

But in order to find out about the origin of the moon and about our own origins, we don’t have to send up people – you could send up machines and robots. Why aren’t they good enough?

Robots can bring some information back. But humans, with their specific capabilities – cognitive, sensory and manipulative capabilities – are so unique that they cannot be replaced, at least today, by a machine.

Computers and robots are replacing us in all the technological fields. And they’re doing a pretty good job with satellites, also.

But not in this combination. Just imagine if things do not go as planned – in order to repair systems, in order to react intuitively to a situation that was not known before – this is still not possible with a machine. Humans are very unique in that respect.

But that means the European space agency is still sticking to the plan to send a man to the moon, and maybe to Mars?

We are currently preparing a program to send a so-called lunar lander, to the south pole of the moon in order to develop the necessary technologies for precision landing, for obstacle avoidance, also for some scientific objectives that we try to find out. And also the same is valid for Mars. But the alternative goal, of course, is that humans will follow, to the moon, and alternatively, to Mars.

Should we maybe better cooperate with the Chinese, then, instead of the Americans?

Well, obviously such exploration endeavors are very expensive, and therefore it is very good to do that with international cooperation. And I don’t want to ask the question: either the Chinese, or the Americans. I hope that once the time comes, we do that all together.

What’s the biggest challenge to bring a person up to Mars?

There are still some hurdles that we have to take in developing technologies, for example, related to propulsion, life support systems, the overall logistics, and of course cosmic radiation, which is a problem once we are on the trip to our neighboring planet. I have no doubts that these technologies can be developed, and in fact we are using ISS already today as a platform for the further development of such technologies that we are ready, once the time is there, to send people to Mars.

And in terms of the cosmic radiation, is there a chance to shield that, actually?

Yes, for example, we are developing new materials, light-weight materials, that can shield such spacecraft. Of course, we can not use lead for this purpose. There,I think there we still have to have more advances. But again, ISS is used already today for exactly this purpose.

But then, actually, to get onto Mars you’d have to have a station on the moon first, is that correct?

That is one option, there are various scenarios possible: launching from earth orbit, meaning assembling a spacecraft from earth orbit, and launching from there. Or launching from the surface of the moon. There are advantages and disadvantages, but both would be possible.

The last price guess I heard was 400 billion dollars for sending a man to Mars. Do you think society will be able to bring up the money to meet that goal?

Well, I don’t know if this value is correct. But one thing is for sure – this is calling for an extended international cooperation, and as China is now making a big step forward, I think this is a good sign that we can all together achieve this fantastic goal.

And would that be something for you, to go up to Mars?

Oh, definitely. I would dream of being with my own feet on the surface of another planet. But I would be very happy if I could observe it in front of the TV, and see one of our young colleagues stepping on the surface of Mars.

Interview: Ingolf Baur