Life could have existed under Martian surface – DG Interview by Horizon Magazine
They’re sending a spacecraft to check.
There could have been life under the surface of Mars, according to Jan Wörner, Director General of the European Space Agency, which in March is launching its ExoMars mission to find out.
Do you think there’s life on Mars?
‘The definition of life is not that easy, but the real question on Mars is whether there is something that we understand as life, meaning organic material with cells. And, in fact, there is some chance that in the past there was something similar to life on Mars. Not on the surface, we know that, but maybe below it. And therefore the Mars mission, especially ExoMars 2018, intends to drill about two metres into the ground to find out whether there are some organic materials from the past, either still active or just existing because in the past the atmosphere of Mars was quite different from what we have now.’
What would happen if we find life?
‘It’s a little bit of a philosophical question. Are we alone in the Universe? Is Earth the only place with life or not? From a probability point of view, it’s easy to answer because there are so many solar systems in the Universe that the probability that we are the only one is really small.’
How will ExoMars help to expand our scientific knowledge?
‘What I expect first of all is that we will really understand more about the details of Mars, including the question of life, but also what are the geological processes of the past and future on Mars?
‘For instance, what is the exact composition of the atmosphere of Mars? We are using a very special trace gas orbiter to understand the Martian atmosphere, but also to search for evidence of gas of possible biological importance, in other words looking for something we might call life in the atmosphere as well. ExoMars is really looking for the evidence of any type of organic material on Mars.’
You mentioned drilling. Is this the first time we’ve drilled into the surface of Mars?
‘To that depth, yes. It will be the first time drilling two metres deep .’
How far are we away from a human mission to Mars?
‘I don’t believe we will have a human mission to Mars within the next 30 years.
‘Because Mars is so far away from the Earth, it’s not comparable to a trip to the Moon. The Moon is always with the Earth but Mars has its own autonomous orbit so a trip there and back takes up to two years. Now they are testing a one-year stay on the International Space Station, but if astronaut Scott Kelly gets ill he can return within hours. If you go to Mars and after just one week you discover some serious illness then to wait maybe a year to get medical treatment, that’s a little bit dangerous.
‘In addition, if we want to land, we need a rocket to leave the planet again. The Moon has a gravity only 16% that of the Earth, but on Mars it is more than 40 % so you need a much more powerful rocket. Then there’s the radiation during a two-year trip. You are outside the Earth’s shielding, and if you stay outside that for two years you’d better be prepared.
‘And finally, there’s the psychological aspect. If you look up to the sky right now and you see Mars as a small red dot, that’s exactly what astronauts would see, just in a different colour if they look back from Mars to Earth. That is also a big thing from a psychological point of view.
‘But I am sure humans will go to Mars. Humans went up Mount Everest, they go into the depths of the sea. Regardless of when and how they do it, humans will go to Mars, I am quite sure of that. And beyond, but it will take time.’
Closer to home, you’ve said we should build a village on the far side of the Moon. Why?
‘If you go to areas where you have no visibility of the Earth, and you have none of the man-made radiation coming from Earth, from those places you can have better visibility into the Universe. A big observatory on the Moon built, of course, with materials from the Moon, that would be a very nice thing for scientists. The lunar south pole is a very interesting location. We have deep craters with permanent shadow from the Sun and shadow from the Earth, and we also have locations over there where we have permanent sunshine for energy.
‘A village is, to my understanding, a location where different people come together in a small community. And this idea is transferred directly to a Moon village, so I invite spacefaring nations from all around the world to bring their contribution, be it robotic or human, to have this common place on the Moon for different applications. Public and private companies are invited to participate. This is the idea of the Moon village.’
When we think about the big spacefaring nations, we think of the U.S., Russia and now China. How is Europe doing in comparison?
‘Europe is doing perfectly. The European Space Agency has a very nice position in the global space arena because we have very stable relations with the United States of America, with Russia, with India, with China and with Japan. So you could say we are like a broker, a mediator, an enabler, a facilitator of global space activities.’
Has the nature of space exploration changed?
‘Yes. The space race is over. The space race was governed by vanity and prestige for the different countries. We still have competition in space but we have collaboration and competition at the same time. It is a new vision of space that bridges earthly problems. For instance, in the International Space Station we have Europeans, we have Russians, we have Americans all at the same time, while on Earth there are sanctions against Russia. I think we always need, even in times of crisis, something that bridges such crises, and space is the perfect instrument for that because it already stretches across borders.’
You have said you want a United Space in Europe. What do you mean by that?
‘In Europe we have a lot of activities in space. So, for example, the different Member States, sometimes they have their own space agencies, sometimes we have the European Union being active in space, we have the European Southern Observatory, we have the European Space Agency, so my dream is now – and this dream can be achieved – that we bring together the interests of the different entities to really join forces and achieve a United Space in Europe.’
Why should people be happy that their tax money is going into space?
‘What we are spending in Europe overall equates to each European citizen putting 10 litres of fuel in their car per year, so it’s not that expensive. 1 euro invested in space is 6 euros generated afterwards in different areas, for instance in the telecommunication or navigation domains. So there is a return on investment money-wise.
‘But I think also we have to consider that Europe has a long heritage of pioneering and exploration. I hope, I have the feeling and I am convinced – all three at the same time – that the person in the street is really fascinated by exploration. When in the Rosetta mission we landed on Churyumov-Gerasimenko, I got emails saying, “I’m so glad that my money is going into this mission.”
‘In these days of economic crisis, migration and terrorist attacks, we need shared values for the future, and European heritage has some very good values: democracy, freedom, philosophy, art, but also pioneering and exploration.’
‘Regardless of when it is and how they do it, humans will go to Mars, I am quite sure of that.’